I'm more than halfway through RAGE on nightmare, also I've been trying to not use wing sticks, and turrets at all.
I enjoy the fps gameplay, but the AI tells you the gameplay was more designed towards console, with some exceptions.
The worst parts to me seem to be that I don't like the duck+shoot behind a object AI, although it isn't entirely true as the AI
has surprises

I noticed that kiting is easy against mutant creatures, my guess it was
designed this way for consoles, but I'm surprised as I think they didn't notice
on the PC it can be done longer. Maybe increase the speed of certain creatures?

I noticed the player speed with sprint is beyond what I expected, it feels fast, and even
strafing increases your speed (more like ETQW not quake 3). Also rampjumping is still in the game. I have
yet to test anything else, but once a SDK comes out I will.

I can already tell RAGE is gonna have pro speed runs, etc As most of the time
I don't waste time siting back, and I rush the enemy, etc and it gets the job done quicker in most cases

I hope a mod team will create a DM style mod. With a mapeditor, and few cvar adjustments
I can get a feel of what the gameplay could be like