This is a game with a few flaws, but overall has unique features that make it enjoyable!
As for the graphics, I agree that it wasn't that well done. They probably could have done it better (maybe it was rushed). But they had so much areas to play in one game and so much civilians, military, tanks, helicopters, and infected! The powers were way cool, too! Some I barely used, but most were really useful and fun. And the story was interesting and the bosses were difficult at times (which is a good thing).
The gameplay was fun. Going around, killing innocent people for fun, smashing tanks, and consuming people to disguise as them... pretty cool if you ask me! The missions were pretty good, a couple being frustrating. The events were annoying at times... The only way to get a platinum on an event was to put tanks all around a killing event or just by pure luck with the running events. The camera system was a big flaw which led to a lot of frustration with the events. But the targeting system was great.
All in all, it was a great game. It takes a long time to get platinum trophy with a lot of dedication. But it is really fun to just walk around and kill things! The 45k kill trophy is going to need a lot of time... And yet... With ability to shoot from helicopters, run over crowds in tanks, disguise as a marine, and beat the crap out of an infected monster... I would say that is enough reason to play!