Project MMO offers skills and the ability to restrict the use of various things until meeting a certain level in designated skill.
I have set bows to have archery level requirement but I would like to go a step further.
There's a couple different ideas off the top of my head that could be fun and may or may not require somethings on your end
The upgrade slots that are available when you open your bow's gui,
the ability to unlock them via consumable.
allowing for "use restriction" to be put on the item which can have an archery level to use.

the ability to apply level requirements to upgrades themselves.
"if when pmmo is installed and a use restriction is put on an upgrade,
don't allow for placing upgrade into bow"
until level is reached.