The camera, in its current form makes the game nigh on unplayable due to its position.
The problem is, all I can say is that you will get used to it if you keep playing, and when you do there is a good chance you will really like it.
As an exercise, I might suggest loading up the demo as Chris. Clear off the first set off rooftops.
Then stop. Mess around. Try out the controls. Get a feel for the slide moves. Try moving between cover. Fire off all you ammunition at a wall (note what happens when you pull the trigger really quickly. Note how the laser dot moves when you fire a shot. Note how the laser dot moves when you just stand there aiming at something). Pull out the knife and try all the moves*.
(Seriously, as a favour to me, load up the game, equip the knife, hold down LT and then pull back on the left stick and pull RT at the same time. He does a Stab right? Now see how quickly you can make him repeat the stab. Pretty cool right? Then try to kill as many enemies as you can using just stabs! (a good hint there is to use the forward motion you get with the move he does if you pull both triggers at the same time (or if you hold LT then push the left stick forward and pull RT at the same time) to close the distance with an enemy, then Stab him repeatedly!)
Just in case you don't know how, run towards a chest high wall by pushing forwards on the left stick and holding A. When you approach the wall, pull (and hold) the LT so your guy goes in to a slide. Slide in to the wall. Note that your guy goes in to cover against the wall when he gets there. Do this a lot until you figure out how far away from a wall you can be and reach it with a slide. The do the same with a standing forwards roll. Then play through the demo making a point of sliding in to cover as often as possible until it becomes natural. Then play through it again doing the same thing. And again.
I dunno. Did you remember learning to play Devil May Cry? This is a bit like that. I had to spend ages just trying out all the moves there until I got them down well enough to try using them on the actual enemies.
Just... don't think about playing the demo. Think that you are learning the moveset. It isn't all that complex, but don't stop until you can usefully use every move you can find. Quickshots, Counters. Just stand in front of enemies and try to dive backwards out of the way at the last minute.
I think the game rewards this kind of effort, and I like that. You may to.
And once you have learned Chris, you can move on to another character!
*standard punch and follow up with the knife move that you get by pulling RT without LT held down. A standard slash from pulling RT with LT held down. A forwards lung by pushing forwards and pulling RT at the same time with LT held down. A stab by pulling back on the stick at the same time as pulling RT with LT held down (and, and I really, really like this, you can repeat the stab really quickly). And if you pull both triggers at the same time he does a double slash with forwards motion that I believe is homing.
And with LT held down, if you hit A and pull back on the stick he hops back a few steps while doing some slashes, and if you hit a and move the stick to the side he does a sorta dodge around move rather than a dive roll.