oh damn
i never heard of this anime but i like gems and crystals and stuff soooo
what gems and power levels are we talking about?
i.e.:
1. are the gems realistic, like amethyst, sapphire, ruby, topaz, etc, or are there fictional stuff too like unobtanium, nanonium, kryptonite and whatever other stuff? and what are they each used for? (you mentioned that some gems are incompatible with some jobs)
2. how overpowered can one get in the anime? is it like super godly levels or just normal human power? i need to know this because most of my oc's are brutal powerhouses, though i can make clones without some, a lot, most, or all of the overpowered things (this is canonically possible in my own fictional universe the op ones all come from so it's completely fine if i have to do this)