There are a few House Mysteries that either don't make sense as House Mysteries or that just don't seem to thematically fit with what the Order as a whole stands for... I mean, what it stands for from a metagame perspective, as the magi of the Order are, among other things, a chance for players to be the wizards sitting atop their towers (or whichever structure your covenant takes the form of) performing acts of magic that the little mundane peoples can't comprehend, instead of the ones dealing with those wizards and the fact that they have no idea what to expect.
A really big example of this, for me, is one of the Verditius Major Inner Mysteries in HoH:MC, Bind Curse. It really just strikes me the wrong way that only Verditius magi are capable of something like cursing items, despite cursed items being such a popular thing in stories revolving around medieval magic-users. That seems like the sort of thing that any magus should be able to learn how to do, and aside from the whole thing with required Hubris and Verditius magi not liking other people taking their stuff (which other magi can feel too, Verditius magi are just the only ones required to feel that way/have that trait) there don't appear to be any thematic reasons for the Mystery to be limited to Verditius. This seems like the sort of thing, to me at least, that would be a "general" Mystery, that any magus can learn in play or even start with by spending Virtue points.
A few others, for me, are the Charm Magic and Symbolic Magic Mysteries from Merinita, which I feel should honestly be part of Hermetic magic in general if they're Hermetically possible, but I understand this one a bit more due to the Faerie hegemony on anything that helps focus stories in a certain direction.
So... Would there be any immediate concerns, in terms of balance and keeping each House relevant, if some of the House Mysteries (I'm thinking maybe Sensory Magic, Charm Magic, Symbolic Magic, Items of Quality, Bind Curse, and possibly but probably not Bind Magical Creature) could be turned into generally accessible Mysteries, or in the case of Items of Quality and Charm/Symbolic Magic maybe just integrated straight into Hermetic Theory? I don't really have any players that I need to be on good terms with on this right now, I just want community opinions. If I made those Mysteries regularly accessible, would those Houses lose a lot of their current value? (I mean, I'm pretty sure people were still choosing to be part of Mystery Cults even when only the Core rulebook was out, so they'd probably still be played...) Would this have any unexpected effects in the Order as a whole? Do any of the things I want to add in not actually make as much sense as I think when added to the whole picture of the Order?