Since I'm not ready to add completely homebrewn items to my PF2 EC campaign just yet*, I would dearly like to find items such as this in an official book.
Maybe I'll be more open to doing things myself in a second campaign, but I need high-level experience before that.
*) I mean, adding a strange seldom-used story item like a more interesting Grail of Twisted Desires is one thing. Adding an item that introduces a whole new bonus category has a much larger potential impact, and I want Paizo to give the green light first.
I"m thinking of letting casters add weapon specialization damage to cantrips. I don't see a problem with it right now. I think part of the reason they didn't is because casters can do insane damage at higher levels with bursty spells versus martial better round to round damage. But I don't know. it seems cool to let casters use weapon specialization with cantrips.
I did wreck a party with a lich unloading AoE spells on them. I should have known a critical fail on an 8d12 spell would do nasty damage, but it didn't register until my player critically failed and took 110 points of damage when a critical fail doubled the spell base damage. That is super nasty at higher level.
I was reading that cataclysm level 10 spell which does like 21d10 damage. If you critically failed that spell save, ouch. You could wreck a large enemy group.
Maybe I won't let them use weapon specialization. I'll see after they hit lvl 20 in age of ashes and how I feel.