hmm. i'm a fan of fighters myself (lucario, hitmonchan, gallade, breloom-spore). but maybe ice would fit the bill nicely (mamoswine for earthquake, weaville for dark attacks).
if you're absolutely set on a ghost though go with sableye, dusknoir, or spiritomb
and nah keep the shinies. i was gonna release em cuz they've got exp. thought you'd want em more.