Consider some of the peaceful Gouramis. If the tank is placed so that it doesn't get a lot of noise and traffic, a Moonlight Gourami
would be a great centerpiece. If the iridescent white color doesn't do it for you, maybe a Pearl Gourami
would answer. Now, I know diddly about cichlids, but some of the dwarf species - Rams or Apistos - might interest you. You'll have to keep up on water changes, though.
I've found platies to be pretty hardy and fun. They don't last as long as neons, though. If you do go with Platies, I'd suggest you get 3 males and 6 or 7 females. They are at their best in groups of 10 or so. With that the case, I'd consider making my school of neons as large as possible.
For the bottom, if you had smooth or fine substrate, get you some cories - 5 or so. Once they are mature, you might even get them breeding (though the fry will be unlikely to survive in a community tank unless you have a pebble bottom.) Lots of different ones to choose from. Since Neons show up best on a dark substrate, I'd go with white cories, and probably yellow, twin bar or mickey mouse platies or the Moonlight Gourami
, over a black pebble substrate planted with some swords, and with a dark sand beach separated out with some rockwork - preferably petrified wood.
One other think that would be neat to ad would be a small pleco of some sort. One of the bristlenoses would be best, or a Clown Pleco
. Either would work, and both require driftwood in the tank (which will stain the water and enhance the color of the neons.)
And skip the salt. Neons don't like it, nor do cories, plecos, gouramis, or dwarf cichlids. Platies do like it, but they don't need it.