Re: should I forward face him?
No, you're not horrible for wanting to FF him. But I agree that you shouldn't.
The car seat cram is tough now... just wait until he is FF and can slither down on to the floor of the vehicle and slide away from you. >.< At least when RF you have him confined between the seat and the vehicle.
Try maybe teaching him to climb in to the car seat to avoid hitting his head.
Try maybe holding him in a sitting position (from hip carry, swing the back leg forward so he's sitting on your arm with both legs forward) then slide him in. It makes it a lot easier to get the harness on before he can go stiff-as-a-board on you.
Try maybe special car toys he only sees in the car.
Try maybe gadgety things to keep little hands busy. Shoe laces intertwined through cardboard or foam with various holes could entertain my 20mo for hours!
Like you said, he doesn't want to be confined. It's a age thing. It won't get any better if you FF him. I can so very much relate though and I promise this too shall pass.
(CPST momma to an Amazon child ERFing in a compact car as well as a 20mo boy)