Play sand is great. $3-$5 for 50lbs.
Well if you have the lights then go for any plants you can wedge somewhere or keep them down. I was just trying to say that most people who go towards cichlids (generilization coming up, not everyone is included.) doesn't get those huge expensive lights for plants because they focus on the cichlids and don't keep a heavily planted tank. So if you have the lights your options will open up a bit more, i was just saying "generally" you don't see the big light kits in cichlid tanks. Excluding of course the real heavily planted amazon type tanks.
I'm more of an african guy myself so i would suggest some kind of african. Yellow Labs would be a pretty good choice, pretty common and good to see across the room.
As froggy says tangs would be good. Brichardis are a good choice, might even get a spawn soon after too.
I also suggest what froggy says, go to the store, see what grabs your eye and come home with its name. Or browse through our profiles...i believe we have quite a number of cichlids listed that would go well.