The irony about Resident Evil 6 is that it's not a bad game, the controls work great, it's visually stunning, and the sound and music is great.
What makes it the weakest entry is simply because that it's the polar opposite of what made the series so great to begin with. I wouldn't even call this an action-horror game, it's more like an action game with a horror twist.
Leon's campaign was pretty fun, and the most suspenseful and creepiest out of all. Mostly because the classic zombies make their return which was a good decision, that and exploring and fighting your way through the infested cities, catacombs and caves was fun.
Chris's campaign however honestly wasn't that fun. It felt like I was playing a cheap version of Gears Of War, that and Chris was kind of whiny douche bag throughout the whole game.
Jake's campaign was pretty much the same as Chris's except with more of an emphasis on melee combat. So nothing special.
Last there's Ada's campaign, which once again plays out like Chris's and Jake's, with the exception of Ada's grappling hook gun which was fun to use.
I think they should've just stuck with regular zombies. Zombies that run at you with machine guns and knives aren't scary, they're just annoying and tedious to put down, especially the ones with sniper rifles.
The boss fights are very underwhelming. For starters there are only a handful of bosses which means you'll end up fighting the same boss several times throughout the course of the game. Plus there's hardly any strategy when it comes to fighting them, you just spray bullets everywhere and eventually you win.
The puzzles have no thought put into them and there are hardly any at all, which is disappointing because I've always liked Resident Evil puzzles.
The plot itself bad as well, but you realize this only after you best the game. When you first start playing, you're of course interested and yearning to know why these events are unfolding. But once you finally beat every campaign, you're left with a dumb explanation for the everything that happened, and a pointless epilogue.
Overall, Resident Evil 6 is an ok game, but your left with the feeling that it could've been so much better. If it had just starred Leon, then I would've liked it more, because his campaign is the only saving grace for this game. Everything else just feels like a scrapped action game that was put in just to appeal to more people.
Hopefully they'll learn from their mistakes and make next Resident Evil better.