I had a pick that I equipped to yoru but it dropped the dps of her R from 10k to 8k and her standard attacks from 600-660 ish to 590-600 ish.
Instead, I tried giving it to linette and this time instead of speculating without precise numbers, tried to get some numbers on a table.
The sample size is very small but I think we can conclude that getting one of the R tools instead of the UC weapon for an upgrade heavly depends on the substats obtained, it may be obvious looking at the overall stat increase but I wanted to verify it.