I'd like a small barn, maybe 6 stalls at most, a tack room, and an office area or place to just hang out. I like this one in the picture as I like the stall to turn out area. The only thing this is missing is the indoor riding arena. I'd want water available indoors and it would have to be heated. But with plenty of ventolation and light. A hay storage room would be nice too.
I like this one too, only there would be fence all around with gates to different turn out areas. Storage on right, stalls on left with aisles in both and center riding arena. That would be cool. Quite frankly, at this point I'd be happy with a small barn and an adjacent riding arena.