So, you can plug the + enchantment separately from the other bonus effects, yes?
All randomly generated Superior Potency VI items in the game are +3 weapons. Could you make one that is +1 and drop the ML to 12?
Edit- Ok, so I lied, there is more than one muse in here:
Will crafted items be eligible for Risian upgrades? Presumption would be no, since they aren't randomly generated, but I don't know if the game will have any indicator between a crafted item and one popped up by the RNG (as opposed to named and GS, which are distinct even in the item description screen).