I'm 5'11 and about 175 lbs and I am wondering...
I'm 5'11 and about 175 lbs and I am wondering what size I would be that is loose (non-restricting in arms) but not super baggy or huge?
Large will be a regular fit. It won't be restricting, it will be a little loose like any standard snowboard jacket. I suggest stepping up to XL to get some extra length out of the jacket. I'm 6 feet tall and wear XL jackets. They fit baggy but not huge, don't constrict, and look tons better than the standard large.
Mr.Shredwise pretty much summed it up. You should have success with a large but XL may be the Golden ticket.