Bonuses, I think, shouldn't be offered via feats, barring situational bonuses that generally overlap(if at that), while class features, I reckon, are the domain of multiclassing, new options are the key. Though a limited level of class feature grantery is probably acceptable(level appropriate in power(damage, attack bonus, etc) but entry level in complexity, like say a 1st level psionic power at your HD in manifester level).