Yeah, I was never sure it held water properly. When your core argument turns into "Do they need to be a spellcaster, or did the writers just assume that anyone casting a spell would be one" it's on thin ice. Oh well, Metamagic Effect still works (doesn't care who cast the spell, just that it is present). Leaves you with only one shot at Persisting 1 round spells like Wraithstrike, but it'll work. Have to save Co-op for an actual spellcaster.
Interesting about the Wand modulation. It never occurred to me that you could make a item holding an infusion, what a simple thing to overlook. Huh. I've read the handbooks countless times, I'm now amazed at my own ability to avoid realizing this until now. Artificer really is the person who says "screw the rules, I have money" when you start mixing all these ingredients already mentioned.
Unfettered Heroism is such a silly spell. Like, not in itself and not within the context of using it for the basic functions listed in the ECS. But combined with everything else keyed to it... Wand surge working with Staves is probably high up on that list. Then there's Primordial Scholar as well, practically giving you infinite 1st-5th spells.
My idea actually came from trying to figure out a way to have a Blade of Orien that could be very liberal with their teleportations and looking to UH combined with Unlock Dragonmark. Unfortunately, Orien's Fury is keyed to whenever you use your Dimensional Jump as a swift action, and using Unlock Dragonmark is a standard action.
I wonder if there's any substance to a Decisive Strike Monk using UH and Dragonmarked Fist.