Are you opposed to all damsel fishes? If not try some yellow tail damsels(chrysiptera parasema) though, make sure it is parasema and not the similiar looking cyanea. The latter is the blue devil(still with yellowtail but has black head spotting) but very aggressive. Allen's Damsel i hear is a good choice as well but i think they are special order only, atleast in my area.
Threadfin anthias are really pretty as a school and can be grouped but, usually as a hareem.
Bangai as i understand dont really school in tanks, they just... well disperse. Mostly it seems they stay together in petstore aquaria only because they are crammed in a 5 1/2 gal space. Im not sure on pajama personality though
Unfortunately with salty stuff the fauna that does school in nature grows to large to accomodate their schools in anything but public aquaria... unless you have $30-50,000 laying about hehe.
Heres a short list to avoid putting more conspecifics together: most damsels, gobie, blennies, tobies & other boxfish.