I've boarded Dusty once, shortly after she showed up, no choice vacation already booked. I visited the place unannounced and they gave me a tour. I had brought Dusty with me just to see what she would think of it. I was impressed that they would not let me bring her in the back without checking her for fleas first, and I was not allowed to put her down on so much as the counter without proof of vaccinations. That put my mind at ease knowing they check everyone that thouroghly. They also checked her for fleas before she left.

I had paid extra for more play time, but turns out I wouldn't have needed to. Dusty had a habit of pawing at doors/walls when she wanted them open. One of the girls there felt so sorry for Dusty pawing that she got her out every time she pawed. Needless to say Dusty got quite spoiled there. The girl even cried when I came back a week later to pick up my kitty. lol

After that if I had to go away I'd have someone stop by twice a day for feedings etc.

Since Jack now has to have medicine and eats 4x a day I have someone either stay at the house, or work in two petsitters who both stop over 2x a day to cover Jack's feedings/medicine schedule. It's very complicated and a hassle, but it's what he needs.

Back to the original question; what would I want for my kitties? Assuming money was no object....

Cat tree
Hammocks
Window with birdfeeder outside
Tv or radio playing
Some kinda of cubby/hidey hole
Lots of play & brushing time

Something like these...(funny not one is in the US)
http://www.lavendercattery.co.nz/boarding.htm

http://www.norfolkcattery.co.uk/

http://www.bbcattery.co.uk/page3.html

However given that I'm not rich....

With Dusty I settled for a very large, hand built kennel with a wire front, shelves, a hidey hole, sneeze guard, and a very clean, well maintained facility.