A slight update on my impressions: after plugging in a 360 controller, my enjoyment of the game improved substantially almost immediately. It's obviously a game designed be to played with a controller as opposed to a keyboard+mouse set up, and it doesn't seem like they really changed anything in the PC version. When playing with a controller, many of the systems also feel more polished and refined.
The combat is still pretty awful, imo, so much so that I almost exclusively use hand-to-hand combat now. It seems poorly designed in this aspect especially, since weapons actually cost money to upgrade and customize, and ammunition is finite within missions - yet it is the unlimited and free melee attack which is the most powerful form of attack in the game. Kinda weird. There's pretty much no reason for me to ever invest anything into firing bullets at this rate. Even Chainshot isn't as effective as just rushing up to a group of 3 guys and just punching and kicking the shit out of them.
I'm really digging the new characters being introduced as the game progresses though. Interesting personalities, and having individual reputation stat tracking for each character/faction is a huge improvement over stuff like ME and ME2's overall morality scale, since it encourages me to experiment with different behavioral patterns with different characters without feeling that I have compromised my overall character's role playing aspect.