TwoSix
Dirty, realism-hating munchkin powergamer
Yea, you're right, Magical Initiate is probably a good comparison.That would be like Magical Initiate giving access to all the level 1 and 2 spells and 1 spell slot.
Probably not overpowered, but kinda undermines mutliclassing.
Maybe make it as:
Select one martial weapon and two simple weapons to be your readied weapons. You gain the draw/sheath as part of an attack ability for those weapons, and access to the adept feature of each of those weapons.