What about threadfin cardinals? I thought they were the "en vogue" schooling fish of the day (ie. no issues with hardiness like anthias, jumping like wrasses, or turning on each other like chromis). ? (I could be wrong but I thought I read that's what people look for these days when they want a "schooling" fish..)
They look a little like tetras to me, but if they are a true schooling fish then you can overlook that a little, IMO.
(Well, I happen to LIKE tetras, so maybe it's a bonus..)
Apogon leptacanthus
http://www.aquaticcommunity.com/mari...rdinalfish.php
http://www.wetwebmedia.com/cardinal.htm
Other possibilities include other cardinals, like pajama cardinals, I think I've heard they can school. (Sphaeramia nematoptera)
HTH