Thanks for the mod, I've been thinking for a while about creating a some sort of "Quality overhaul" mod that will make the quality mechanics more user-friendly and more interesting, but I hope for the early release of 2.1, in which I think the developers themselves should try to fix all the sharp corners of this mechanic. This is a well-known quality problem, that low qualities are not as useful compared to the difficulties that cause the creation of these items. And many people just skip them and craft legendary items right away, especially since the game has two methods(exploits) that make this task much easier.
But your mod, in my opinion, does not improve this situation, but worsens it. Instead of 5 different qualities of items, now we have to think about what to do with 10 different qualities of items. Moreover, these additional levels do not give any bonus at all. That is, they are literally meaningless and will only fill the chests, and it scares you away from quality mechanics even more.
I suggested it on the forum (https://forums.factorio.com/viewtopic.php?p=682027) and the developers implemented this in the API in version 2.0.69, such a concept as prohibiting jumping over several quality levels. I think this is a more concise solution to this problem.
Now it is possible to limit the possibility of jumping to 1 or 2 levels at once and compensate this by increasing the chance of this jump.
Another more elegant solution in my opinion would be increase the chances of different qualities by different values. In your mod, you increase the probability to 20% for all levels and compensate this by adding more levels. But instead, you can change the chances to, let's say:
- Normal->Uncommon to 20%
- Uncommon->Rare to 10%
- Rare->Epic to 5%
- Epic->Legendary to 2.5%.
It seems that in the end you will get the same thing that you have achieved in this mod, but without creating 5 unnecessary qualities.
