ACU's are a modern cut, much more comfortable I found.
I myself use combats, for lack of a more accurate term. The crye style within integrated knee pads.
If you're prone a lot and the ground is brown, you'd actually be better off with woodland marpat.
Honestly camo doesn't make much of a difference when you're moving or outside of your environment, so really you just run with whatever you think will come in handy most often.
ATACS-FG pretty much comes off as multicam from a distance
And personally I've always found cadpat to stand out, but I'm used to prairie terrain which has much brighter greens than the canadian shield area.