You could do a couple red sevrums and some rams or apistos??
i would try a pair with some targets/schoolers.sajicas,cutteri,convicts,etc.many in that group stay 4-5 inches.just 1 pair.maybe start with 5 or 6 to get a pair.as targets get a small group of:swordtails,platies,red eye tetras just 1 species