I feel you. We already have an arena, although the footing needs work, but the dust in the barn aisle was choking and I was over it, after 3 years of raking screenings dust. $5400 later, I have a beautiful aisle and I regret nothing. The original quotes were like $40k including the stalls and that was definitely not in budget so I had given up (it’s a 20 stall barn). So the right thing may come along!
I am excitedly following your tack room/feed room build. Right now I am using a combo of some empty stalls plus the shed, but I really want to do something different. Does it work for right now? Yes, but it feels janky.