That's wonderful progress!!!
Is the 6 oz (roughly) just formula, or a mix with breastmilk? I think the extra pumping is a good idea if you have time, since the formula is milk that you aren't making, kwim? If you can up your output to the pump, you can gradually replace the formula supp with breastmilk for the finger feeds, and then transition (either slowly, or quickly if he's up for it, which he very well might be!) from giving it via supplement to direct from the boob. If you are really concerned about boosting supply, you could try fenugreek and blessed thistle, or eating loads of oatmeal, just to give the pumping some assistance. Good info here http://www.kellymom.com/herbal/milksupply/fenugreek.html and here http://www.kellymom.com/bf/supply/index.html
You could also try giving the supplements via supplemental nursing system at the breast. Essentially, take your finger feeding tube and insert it in his mouth while he's latched on, or try to latch him on with it taped to your breast, if you can manage that - it can be tricky to learn to use and get baby to accept. He might be expecting the faster reward of the supplement and still get frustrated at the breast during those slow-flow times for a little while...the supplemental system would help with that if you can work it, and the you can start holding back the supplement gradually so he takes more from the breast and gets used to dealing with times of day where you aren't quite as full (which is normal...late afternoon and evening are my slow-flow times).
It sounds like he has improved by leaps and bounds, I am sure the trend will continue - it's just ironing out those last little wrinkles, and your lactation consultants are probably right, it will all even out with a little time :) Great work, momma!!