This game was heavily hyped and I feel fell a bit short of it, but looking past it it's still a great game. Campaign mode was a nice way to get acquiainted with everything, although I suggest playing the campaigns in the order of Chris>Jake>Leon>Ada. I'm happy they kept backtracking and puzzles to a minimum as I found those incredibly annoying in the early REs. Some things they should not have gotten rid of would be the choice of a variety of guns and treasure hunting. The vehicle portions of the game as well as some of the fixed camera angles were downright frustrating and should've been made a bit easier or axed completely (fixed camera angles definitely should've been axed). The "abundance" of QTEs you hear about in this game are not nearly as horrible as people make it sound in my opinion. I will say though that this game, like RE5, really wasn't scary. I think we're so de-sensitized to the whole zombie thing now it's hard to scare us with things like that.
I love the addition of the melee system and all the freedom of movement in this game. It feels like I can breathe better. Jake's hand-to-hand ability is really fun once you get the hang of it. There is a bit of a learning curve with the new controls but they feel great after you've accustomed yourself to them, save for the cover system.
The real selling point of this game though is the mercenaries. Playing it after the campaigns leads of hours of fun and addiction, even moreso with a partner. If you're not sold on the campaigns, at least give the mercenaries a chance. I still play it even today and I got this game since launch.
Don't listen to the naysayers of this game. Try it yourself with an open mind and you'll see the great value in this game. At the very least in the mercenaries anyway.