Buenos Aires Tetras are nice, I would recommend these also. Additionally I would recommend just about any hi-bodied tetras such as diamond, lemon, or black skirt tetras - their body shape helps prevent them from becoming a snack later. I keep a few common black skirt tetras with my South Americans, and they hold their own just fine.
i use buenos aires tetra with my 9" midas and juvie angels, i currently have a small shoal of about 18 but im going to add 20 more and a shoal of 20 congo tetras. both get large enough to hang with some larger cichlids and are deep bodied enough to avoid predation.
I wouldnt advise putting them with jags, umbees, trimacs, etc. i wouldnt want to risk tetras wish fish like that.
I have 25 lemon tetras in my 120 gal. with my discus. they school most of the time and are much prettier than at the lfs. I like natural and the congo's would'nt look right with your cichlids. if you have lids for your tank, a group of hatchett's would look great as they stay at the top of the water column. I would love them but my tank is an open top and these fish don't jump, they fly.