Ok, the recommendation is to return the crafting system to same RNG system that has been done to death in other games. Gather the materials, stick'em in the box and press button and pray. Alright, I get where you are coming from. This crafting system is simple little math mini-game with fixed predefined outcomes. So, the best of both worlds would be to keep the math mini-game but change the stats on finished products. Change them from fixed values to an RNG range.

Adversarial discussion, often mistaken as an argument, is an effect methodology to elicit productive ideas and clarify points of view. No one is right or wrong, just offering points of view.

Many players like the math mini game. Many player like the reliability of quality of the finished products.
In keeping with the NQ / HQ, it would affect the ranges of the RNG. The more completion you achieve, the higher the base stats could be thus improving the reliability of quality. And still maintain the ability for ultra-rare superior quality items.

e.g.
Weapon damage ranges: 50 - 60 at 0%, 52-60 at 25%, 54-61 at 50%, 55-61 at 75%, 56-62 at 90%, 57 - 63 at 100% : Or, some kind of improving sliding scale.
Then apply this same type of logic to all applicable stats.

The goal would always be to get 100% quality but that will no guarantee an optimal outcome. And, due to RNG, a lower quality out come could still produce a weapon of the same quality as the 100% quality craft.