Totally get it. You’d be there FOR EVERRR with a 21!!!
But my dad lives in a place like you described. Huge tree ring in a tiny yard, in front of every home. They mow with 60 Toro’s and it looks terrible. They can’t maneuver without tearing grass, and they miss a ton of turf because it’s soooo tight in there. I gotta stop over with my 21 and clean it up for him all the time.
To answer the OP’s question I’d say my accounts would dictate what I’d want, and it would be a 61 vride. Then I would tailor all my growth towards that, until I was forced to add a mower.
Only our best guys ride the front yards as it does take extra training to be proficient and not tear things up.