I shot 410-415gr easton classic hunters in a bear LST at 60/29 and those were right about 280fps. Sevr 1.5 never had a problem going through PA deer.I've always shot the heaviest arrow I can get to 280 fps. For me, this is 440-450 gr. That's my all-around arrow.
For midwest whitetail specific, I may shed some weight and go faster next year with the new Easton 5.0. Im thinking maybe 415 gr around 290 fps.
For these Kansas whitetails, a smaller gap 2-pin would be desirable as long as I keep my arrow over 400 gr. I started at around 380 gr at 305 fps. In hindsight, that was a pretty sweet set-up, just not a lot of passthroughs. (I think shot angle makes a bigger difference though.)