That sounds like a wonderful idea. I have the variegated aloe vera as the center piece/show stopper and it grows shallow fat roots so that I can have it in a shallow and wide pretty pot. I have some Dudleya gnoma McCabe 'white sprite' in with it and hope to add some of the Crassula capitella ssp. thyrsiflora (Thunb.) Tölken 'Aanteel-poprosie' if I can ever find it locally. I'm just not sure about buying
plants and having them shipped my one experience with doing that was awful so now I try to stick to
seeds and bulbs.
If you have a fair amount of space you might want your focal point to be a 'Bonsai Crassula'
Scientific Name: Crassula sarcocaulis Eckl. & Zeyh
and then have a carpet of portulaca at it's feet. Mine has bloomed most all of the fall and some during the winter indoors although it has needed pruning a few times.
I hope I've been of some help. Good luck with your indoor garden.