LOL, where you do have a pattern, based on the 'vanilla' weapon, and the ones I have mentioned have fallen out of sync. It seems all your other schematics are on point, it's only the ranged that seem a little off.
Gilded and Gemmed seem to be +20, and Ornate +40. But as you see, those are not quite right.
Ok I see where the problem was, throwing axe, hand crossbows and bolas are supposed to be level 7 items. The Great crossbows level 24 instead of level 27 was probably a typing error So this should be fixed as of now