I was also dumb with getting higher level Sigils. The first option at the crafter was for some special thing, where I didn't have all the mats back then, and the next one was 20-25 (incidentally my own tier, when I first looked), but I just didn't scroll down. I can in fact craft up to tier 100, so at least that part doesn't seem as bad. Skipping a bunch of these lower tiers should speed up leveling the glyphs at least a bit.