Maybe you can add new rib tapes over the tops of the seams with a different type of material (dacron), making them a little wider and gluing them down with Sig Stix it or Balsarite. ???? The Dacron from Aircraft spruce is really cheap, and you saw how it looks on my triplane. Comes in several different weights. I recommend a roller cutter to cut the stuff as it can fray a little.