^^ Yeah, intuitively, I would think spacing the omnis is your best bet, and run them maybe waist-high. For the mics on the drums, I suppose it's worth considering either running the 4027s higher to be further away from the kick, or just consider sticking with the 4022s ORTF so that at least relatively the pattern is less center-heavy.
You could also experiment, instead of splitting the omnis, with splitting the 4027s. That would give you less of the drums, too, compared to the omnis, although I'd think the omnis would give a more pleasant and natural sound in that config.