I went back and reread this.Yes! I agree, I would like to keep my fps over 3k MV and ideal would like to push 3100 or a lil over with the 200-215 bullets. I want a Sherman but I just don’t want to fire form, I know a lot of ppl will say it’s easy and that I just do it during barrel break in, I still don’t want to...
You're going to need a hot powder like n570 to get anything close to your goal with a 30 nos. And at that, you'll be hard on brass and barrel.
Based on your goal, I'd suggest the 30 Sherman or 30-28 nosler.
I know you're not a fan of fireforming but knock out 100 rounds of ADG brass and you'll be good for a long time. The other option would be hydro forming of the brass.