My other stadium allowed a ton of homeruns being at 5279' and having 2' walls from foul pole to foul pole.
My newest one is the opposite of that. Cheesehead Field in the Frozen Tundra of Canada is at 0' elevation, 375'-407'-400'-403'-375', with 13' walls from foul poles to the alleys that taper down to 8' in center. Both of these stadiums are playable in DD!
Most fly balls will be caught if you put Rickey (LF PXP IV: 99 Speed/94 Reaction/88 Fielding), Kenny (CF: 98/94/93), and Byron (RF secondary: 99/94/94) in the outfield. If you don't, have fun chasing balls a long way while any runner with 80+ speed is rounding 2B. Heck, I've hit a triple in the RF alley with 38 speed FS Crochet (SP) and a triple with 30 speed FS Cabrera (SP) down the RF line.
For the vault it is easiest to search by online ID and "competitive safe!