If I had a ten stall barn....hmmmmm.... I'd keep the four I have, add a Friesian/TB cross gelding for jumping or dressage (and magically train myself in how to ride both of those disciplines) a couple of good, SOUND, go along trail horses, don't care what color or breed, a pretty sorrel appendix mare named Asphodel, a big stout palomino QH gelding named Maximus and a gentle black welsh pony/morgan cross.
As far as amenities....aside from all of the usual wash rack/hot water heater, etc....I've always wanted a barn/library to combine my two passions.
1- Rascal (of course) with NO INJURY and ready for the trails!
2- Freisian Mare gentle and willing, trained in dressage (Magically I'd know how to do this on Olympic scale)
3 & 4- Matched set of driving shires or black perches
5- That filly I wanted!!!
6- Andalusian (Mare or gelding)
7- 1 fugly that no one else wants :)
8- Liver Chestnut TWH mare 16+hh 5-6 yrs old (papered out the wazoo but never put in the stacks and crap like that)
9- RMH gelding 5-6yrs old awesome trail horse
10- a pony named Charlie
Hmmm amenities would include indoor and outdoor (covered) arenas
Swimming/therapy pool for the horses
HUGE tack room fully stocked with tack of choice for each horse
Game room for the rainy days (Hey it's magic right?)
2 wagon garage
Separate hay barn, equipment shed (fully stocked w- tractor etc.)
All stalls would have their own paddocks attached
HUGE GARGANTUAN pastures with horse safe fencing and card key locks on all outside gates
Big 1 br apartment over the barn ( I always wanted to live in one of those)
Wash racks inside the barn and outside hot water at both please!
Sacrifice areas for those rainy days
Fully stocked state of the art veterinarian facilities with my own personal vet on call 24/7 365
Foaling stall
Stallion facilities in case one of these changed magically to a nice top of the line stud or I decided on one later
Dream stalls 20 X 20 for each horse
Did I mention I want a feed room that is varmit/bug/horse proof with endlessly replenishing quality dietary items tailored to each equine?
A treat machine that dispenses apples, pears, carrots, mints, and those apple treats Rascal loves so much....that never runs out.
Money machine with an endless supply of horse dollars to keep it up to date, fully equipped, spotlessly maintained, and where the equines and myself never wanted for anything.