Still trying to get my friends to do a Playtest, so can’t say I have anywhere near the experience the rest of you have had, but did want to chime in on this as resonance has been bugging me a bit since I first heard about (sometime during the GCP Playtest).
As it was described at the time, most of the time resonance won’t affect you. But then why have a new complicated system that won’t have much effect? I understand the issue they’re trying to address - at least I understood it as being directed at abusive / excessive magic item usage, we can break the game difficulty. But I think the OP’s post is spot on - I would rather just have a limit on the number of magic items / potions you can use in a day, rather than a chance-based system.
Question is how easily it can get unwound, considering that a lot of classes are probably balanced by the resonance rules (eg Alchemists et al with more resonance than other classes), and some classes (again, eg, Alchemists), that rely heavily on resonance.
On that, my limited experience with resonance so far is just trying to prepare an alchemist. Resonance and batch prep of alchemicals and then you need resonance to use them too... it just kind of did my head in, and I’m sure I don’t understand the rules yet - which seems like it’s just a bit too hard.
I wonder if one of the things I’m finding makes it hard to understand is that it’s not entirely clear what Resonance is intended to reflect? Other than it’s “You’re innate ability to use magic items”. Why is it innate? Why can’t it be learned (or maybe it can, cause Alchemists get it that way?). It’s almost like they’ve added The Force to the game, but haven’t explained what The Force is or how it works. We need old Ben Kenobi (or at least his equivalent in Golarion) to explain resonance and why people have it in different measures. Without something to grasp on to it makes it harder to accept the mechanism it’s reflecting, and this makes understanding the rules and how they work harder, and also undermines “believability” (yeah, I know it’s a fantasy setting, but there are internal rules to comply with as well).