They would be healthier and happier, over all, in bigger pots. Not sure if you'd be better off or not, transferring them now that they are in flower though, could be fine, IF you were very gentle, and it was a good smooth re-pot, but plants are a lot more finicky once they start to flower, since they are focusing most of there energy on the next generation, instead of there own well being. I'll defer to somebody with more grow years on them than me, on whether to re-pot, or bring to harvest in the buckets.
Usually I like transplant from my 5 Gal about maybe 18" tall or so, basically when branches are about to reach edge of pot, I transplant, before the roots hit the edges.
Ya, hit them with the BT, I think, spider mites first, but you want to get rid of those little F_-_ers stat, to.
Usually pests aren't quite that bad, but sometimes they are....
What soil ya using. Also, the healthier you can keep a plant, the better it will ward off the little critters. The better your soil, when growing in soil, the healthier your plant, and less troubles for you.
They don't look bad at all, considering the bugs, and I'll bet ya get a nice harvest from them! Just get them pests knocked out if you can.
Best luck!