hey zoo
A 55g planted with dwarfs will look great. Just keep in mind that although their bodies are dwarfed, their territorial requirements are anything but. A 55g is just big enough to keep two pairs IF it is heavily aquascaped (and I mean heavily). Make sure you purchase both at the same time. Making two cave/rock sturctures at opposite ends of the tank, with some kind of visual screen between the two would be my suggestion. As for substrate, go with ecocomplete or onyx sand. Most dwarfs are somewhat geophagus, and it's fun to watch them sift sand.
I would encourage you to go with apistogramma species, as they are hardier and IMO show a wider range of behaviors than the more common rams. They are more expensive, and not very much to look at in the store. However if you give them their own tank for a few months they will undergo the most dramatic transformation you could imagine.
Angel fish, and tetras will round out the tank nicely, and give visitors something to ooo and ahhh about.