I don't follow Formula 1, but I do have an interest in racing games. I recently played F1 2012, so didn't take too long to adapt to F1 2014. There's an impressive amount of customisation options, so you can tweak the difficulty to how you prefer. You get the usual assist options like ABS, Traction Control, Racing Line, Rewinds and Autobrake. You can now change the quantity of Rewinds to unlimited. However, the rewind window is quite short so you have to be quick at activating it.
There's no KERS, but DRS is still here. I assume this removal is due to an official Formula 1 rule change. DRS allows you to gain extra speed on long straights as long as you are a few seconds behind the car in front, and it isn't raining.
There's still the short 10 race campaign mode where you do a 1 lap Qualifying lap, then a short race. You get to pick a rival, it's best out of 3 then you can join their team if you win, and that process repeats 3 times.
The main Career mode has Practice, (multiple) Qualifying stages and then the Race proper, with much longer lap counts. You only get to switch teams at the end of the season.
There's two time-based modes; Time Trial and Time Attack. Time Attack has a limited set of challenges but they are the same thing really; try and beat a target time without driving off course. In Time Trial you have the full set of tracks to choose from, and can choose any car.
There's a set of Scenarios where you have to catch a certain car, defend your lead etc with only a few laps of the race remaining.
The game still has the random stuttering which has been in the previous games. It also has the bug where it decides to launch windowed at the lowest graphical settings. Since there is no option to enable full screen in the UI; to fix it, you have to find the config file in Documents and change the fullscreen attribute to true. It's weird how years have gone by, and they haven't fixed these issues. I encountered a few random crashes, and one time, the Flying Lap option spawned me onto a barrier, ruining my vehicle then completely froze.
As far as I remember F1 2012, not much has changed here, so your value depends on what prior Formula 1 games you have played.