When I built my drag frame from a stocker, we removed all of the straight frame tubes one at a time and welded back in chromoly tubes. We also used 5/8 chromoly on the sub frame, all custom. Get rid of your stock foot peg mounts and get some round aluminum turned down for a tight fit and stick them in back frame tube. This works good if someone gnarls them for grip. We also removed all of the gussets, every single one, but my bike only went straight 300 ft at a time. We also built custom a arms out of chromoly with custom spindles. Built a steering stem from chromoly also. You can save a bunch of weight there too. On a side note the owner of the bike, was 380 lbs and he occasionally raced it when I had other plans. In the end it had a 580 on nitrous and never hurt the frame and this thing got beat up with his big ass on it.
Frame is looking good tho. Just giving you some suggestions not critilizing anything your doing except for have a purple frame! HAHA j/k. Looks good!