I've only played a couple of hours, I hope to get some more time on the game tonight after work, however I've found the driving to be a huge improvement over GTA IV.
The damage is fine for me, slight knocks and bumps wouldn't cause your car to buckle in, and I even had several occasions where I considered an impact to be light to find I'd knackered the lights and bumper. (Much to my dislike as it was a classy car).
I'm only early on and I've yet to find something I dislike. I've seen loads of posts where certain events, features etc... have really destroyed peoples immersion in the game, such as the flashing when shooting someone. It honestly didn't even register with me as a problem.
However, as I say, I'm early on in the game, but the neat little touches that they've obviously spent a long time thinking about are just mind blowing. I know changing character is a basic activity, but I love the camera zooming out and back in, just love it.
Anyway, just my view, driving, damage, map, activities, missions, graphics, sound, shooting etc... so far I have no issues at all, I'm instead totally absorbed in the excellence presented to me. I honestly don't know what people expected?