(This is my perspective as a gamer who originally cut his teeth on the NES, fully enjoyed the $*#& out of the SNES, drifted over to PC gaming when the N64 turned out to be an empty wasteland for RPGs, then stumbled back into the world of Nintendo with the 3DS. I still play PC games, though.)

What is the NX?

I've been a PC gamer since 1997, so I was an outsider of the console world for nearly two decades. But even I knew what the Xbox was, what the PS3 was, etc. What was the Wii U? I honestly thought it was a screen controller upgrade to the Wii. What was the 3DS? I honestly thought it was a 3D upgrade to the DS. If NX is not the real name, it needs to NOT be Wii X or some other stupid add-on name! Defining a console starts with the name. If no one can hear or read the name and know what it is, you've already lost. Give it a well-defined name, Nintendo! Stop saving money on signage by recycling old names! Hopefully the Wii U was a valuable lesson here.

Raw specs?

I've been playing Starbound on PC lately, so clearly I'm no graphics whore. The NX doesn't need to be on par with Microsoft's Scorpio or Sony's PS4 Neo to be successful. It should, however, be on par with the original Xbone and original PS4. The reason is simple: game devs will be forced by Microsoft and Sony to make games that can still run on that original hardware, regardless of whether or not their games also take advantage of the extra silicon in the Scorpio or Neo. This is the promise that Microsoft and Sony have made to their customers. Sure, they will eventually be forced to break that promise in the coming years, but until then, Nintendo can seriously cash in on multi-plats if the NX is at least as powerful as the original Xbone and PS4. As long as console devs are forced to support that level of hardware, Nintendo can join the party and snag some ports without even trying. With even a modicum of effort, as Nintendo seems to be doing, they can likely snag more than half of all future multi-plats!

Storage cap/format?

If the rumors are true, we could see a release NX with a mere 32GB of built-in storage. Meh. But what really matters is how that can be upgraded. If customers can buy off-the-shelf storage devices to expand the NX's capacity, I don't think Nintendo will have a problem. If the NX requires a proprietary storage device (stupid PS Vita!) or if it can't be upgraded at all, Nintendo will have a problem. I doubt Nintendo would mess this up, but it bears mentioning because of the stupid arbitrary 32GB microSD card (supported) limit on the New 3DS. "SDXC UHS II" is all I will say.

Digital Software Management

Ditto to what everyone else has already said about not re-buying games. But I will go a step further than that. Forget about matching the PSN marketplace or Microsoft's store, what Nintendo should really do is look at what Steam and GOG are doing for cloud-based PC gaming. Nintendo needs to care more about multiple devices, multiple accounts, shared households, and unified digital software management. Steam allows me to share a single PC with multiple people/accounts, have games installed from multiple people/accounts, and only those games associated with a particular account are playable at any given time. Likewise, I can spread my games across multiple PCs, have them download updates and sync saved games simultaneously, allow me to go offline with my laptop (useful for airplane gaming, for instance), but only allow one device per account to be online (single or multiplayer) at any given time. Going further, both Steam and GOG Galaxy allow for unified store fronts with access to all online features and libraries from any device at any time. And Valve does all of this while keeping DRM intact. Nintendo! Take a tour of these technologies and learn from them! This weird idea you have that my eShop purchases are tied to a single 3DS, with absolutely ZERO checks that whomever picks it up to play a game is actually me, is a seriously outdated notion that should have died off with memory cards! It would be in your best interests to design the NX experience around accounts rather than hardware. Let me own multiple NX's and share them with multiple people and multiple accounts and multiple game installs per account! If I want to play a game that I purchased, why should I be blocked because I downloaded the game or have a saved game on THAT NX vs this other one sitting here?? If I want to show my friend a new Pokemon I just caught, why can't I just log into his NX with my account, sync my save game, and show him??

Solid Launch

Yep, what everyone else said. The NX needs, needs, NEEDS to have a good launch! Otherwise... I hate to be all doom and gloom here, but the NX could go down in history as a repeat of the Sega Dreamcast if its launch year ends up being all red on the books for Nintendo. The Wii U has similar sales figures to the Sega Saturn, so I can't claim the naysayers are entirely inaccurate here. Please, Nintendo! Don't suck at this and end up like Sega! Let Mighty Number 9 be your inspiration to not suck!

Games not from Nintendo

I personally thought that Fallout 4 was a horrible bastardization of my beloved Fallout series and I flat out refuse to ever purchase that pile of congealed stench, but hey - some people like it! Some of my friends even like it! I even agree to still talk to them under supervised visitation! My point is that games not from Nintendo need to be a part of the NX line-up, maybe even its launch like others have said, even if I think they're piles of congealed stench. I mean, I won't buy some of them, but others might, and good for them! I have a place in my home for all such gamers, and so should Nintendo! (Well... technically it's a corner... outside... next to my neighbor's house... across the highway... OK, yeah, it's ON the highway, but it still counts!)

Games from Nintendo

Yes. All of them. If you own it, Nintendo, put it on the NX! I want to see the NX be the one Nintendo console to rule them all! Microsoft is saying the Xbone will be the "last" Microsoft console, and Sony may make similar claims eventually. One up them! Make the NX every single Nintendo console from the past and you'll have them both beat! Let your customers vote on which games they want to see next on the NX and then commit yourselves to porting as many as you can! You know fans will pony up and pre-purchase like rabid dogs let loose in a butcher store! You will be DROWNING in pre-purchase funds! Your dedicated porting dev team will be wading through all the cash spilling into the hallways every time they need to go to the bathroom! Make it happen.

Colors, Special Editions, Customization

Ditto on this! OMG, Nintendo, how are you NOT creating a special edition for every frickin' franchise in existence?? How are you NOT spewing out 3DS faceplates in every color from "replacement black" to "obnoxious neon plaid"?? How are you NOT capitalizing on the external customization that your customers so obviously crave?? Going along with what I wrote above for cloud-based NX gaming/sync'ing and cheap storage expansion, it could literally be "I feel like taking my Ice Climbers NX with me today" or "I want to play Star Fox on my Star Fox NX tonight". Dead simple. Games sync'ed across multiple NX's + cheap standard SDXC UHS II cards = Nintendo rakes in the money with colors, special editions, and customization options! This is an easy win, Nintendo. Take it.

Simple Refreshes

I don't ever want to see "new" added to the beginning of a product name again, Nintendo. You done $*#&ed that up with the 3DS. Just saying. Not that I dislike refreshes or "slim" versions, I just want the naming to be simple and effective. Banned words: new, ultimate, extreme, maximum - see? Words like that. Words that are transient in meaning. Don't use them. Also, I would really like to see the NX get a refresh that doesn't change the physical specifications at all. Just cram better hardware into the same shell when the time comes. You can even make it lighter. But if we're talking about supporting the NX for the long haul? Don't mess with the dimensions. All that does it make us re-invest in a completely new array of accessories. Or worse, it makes us NOT re-invest in a completely new array of accessories because we DIDN'T buy the refresh. See how that works? Granted this is mostly based on the concept of the NX being a portable or portable/set-top hybrid, but still, older accessories that don't work on refreshed hardware is flat out annoying on days when I'm in a good mood. Don't catch me on a bad day!

A lot of the early JRPGs were murderously difficult unless you invested hours and hours in the grindfest. (I'm looking at you, Dragon Quest!) This is largely because early JRPGs were based on D&D games, which Japenese gamers greatly enjoyed in the '80s and tried to emulate using the limited capacity of '80s consoles. JRPGs by the second half of the SNES lifespan became what most of us think of as a "JRPG" when they became their own distinct style. (Much like the Disney -> Anime connection.)

Mystic Quest was one of those games where the suits had this idea to "Americanize" the JRPG experience (oh, if only this had been the last time!) and it ended up being a huge step backwards in many ways from even the earlier NES FF games. It was a giant turd of a failure in the US market and to this day is thought of as a black sheep game in the FF series. Later games like Secret of Mana/Evermore (action RPGs), Chrono Trigger, and FF III/6 are far more refined SNES JRPG experiences than Mystic Quest.

The PS1 is actually a great console for JRPGs because it not only became the default console for SquareSoft games (after the Nintendo-Sony fallout) but also has classic compilations of older games, like the Chrono Trigger version with added animation cut-scenes. If you have never played Chrono Trigger or FF7, do so immediately and wash away the odor of Mystic Quest.

I'm going to cheat and say get both! ;)

But seriously, I agree with the above advice that you should wait for the NX reveal before buying anything. There's plenty of info around, both confirmed and rumors, for the PS4 family. You essentially have your choice of the ridiculously likely PS4 slim or wait for the PS4 Neo on Sony's side, and then the NX on the Nintendo's side, whatever that ends up being. But I guess if you're just asking which one to get FIRST, I would say which ever is released first.

Have you considered the New 3DS (non-XL) Super Mario 3D Land bundle for $150 USD? Or do you specifically want the XL size?