If you have one, I'd probably swap one devil dog out for a valkyrie with rocket pods (same price). Dropping two large blasts a turn
With 20 points, you can throw storm bolters on your Devil Dogs. Also, now that bolt pistols are 1 point, I'm getting them for all of my vet sargeants.
Best bet, might be to get camo netting on your tank commander. Just to make him even harder to hit, especially behind cover.