Rules Shifting My Dystopic Campaign

One of my players and I have toyed with the idea of shifting the Dystopic campaign into a different rules set as demons have such powerful, but limited, lores that are kind of inflexible.  The Lore of Storms does a few things to do with water really, really well, but there's a lot of things it doesn't do.  The lores we are currently using are nWoD versions I found on the internet and then tinkered with so that they were more even.  Anyone who's played the old World of Darkness demon could feel the pain of a Devourer of Plants as their powers were incredibly limited compared to the Devourer of Flesh.

Anyway, so I've tossed around the idea of using Mage Arcanum as a more suitable method of using Demon lores.  Sure there are only 10 Arcanum, and 7 Houses, so it doesn't pan out as well on the two distinct Arcanum per house rule.  I figured it wouldn't be such a big deal with my players. 

Then I realised that some of the lores don't gel well with a two Arcana system.  A devil has access to fire, power over magic, and the human mind.  While Mind and Prime cover the latter two, fire falls under the purview of one Arcanum (Forces).  In fact, most of the elemental forces (barring Earth and Water) fall under Forces.  Does this mean that each house should have access to either Forces or Matter?  What does that make the Malefactors of Forge (which would become Matter), if what made them special was now open to half of the Houses?

So then I started looking at legacies.  What if every Fallen had a legacy based on their sub-house and could use those powers even if they didn't have any ranks in the appropriate Arcanum (except for optional legacy abilities)?  A fire devil could wield fire through the powers of their legacy, though in strict and pre-set ways, while still being limited to Mind and Prime Arcanum.  Does this mean that other devils have a slightly more difficult learning flame?  Well, yes, but such is life.

What about Torment?  How does that factor into it?  And Paradox?

Well, I've decreed that Fallen must roll for Paradox with every spell (Vulgar or Subtle) as they, themselves, are abyssally tainted.  I have also decreed that humans can't disbelieve (unless there are large numbers) or otherwise affect Paradox rolls as angels are meant to be able to use their powers.  They can draw their magics from their own selves rather than from the Supernal Realm.  While that power is tainted, it can't be tainted by the human presence.  This gives them more flexibility.  They can cast sights on regular sleepers and other such matters.

Oh, Fallen can also learn rotes, from Mages, books, or their memories (the latter, if I'm feeling kind).

The Fallen's paradox rating also depends on their Torment.  Rather than comparing their Power Stat (in this case Faith) to Gnosis and determing their base Paradox that way, they are to compare their Torment to Gnosis and determine base Paradox in this way.  So as their Torment is generally around 3 - 4, they won't need to worry about Paradox so much.

This also fits a game that's a bit more epic in scope.  While Paradox can affect them, they are encouraged to use their magic in vulgar and powerful ways.  However, since Paradox accumulates for every spell cast (even non-vulgar ones) unless its a Legacy spell, they are discouraged from casting multiple spells in the same scene.  This should discourage them from the "Failed my Roll, Try Again"  mentality that can really cripple diversified problem solving.

I'm happy for them to use magic as a sledgehammer but I don't want them to neglect every skill and merit they have to focus on their lore use.  This is also the primary reason why I'm feeling hesitant.  While I'm sure that my players can pick up the new rules pretty painlessly (in fact, I'll be happy to let my players keep asking "Can I...?" and sort out improvised casting with them rather than knowing it all themselves), I'm not so sure how it will affect the game style.

Mage is quite a "key for every lock" system, and that can ruin games of mystery and exploration.  Between the six of them there is the chance that they could sit in their living room and solve crimes from there using Space and their other lores.  That would be dull.  I've told them as much, so they might choose to limit themselves.  I mean, I don't mind them surprising me with a new lore use and some fancy footwork.  That's kind of what having magic is all about.  I just don't want it to become a boring situation where everything they run up against is hopelessly outmatched.  They're meant to be powerful, but not boringly so.

The rules will be changed in-game as well as out.  I have an adventure in mind where we get to road test the new rules and justify their change in situation.  As the new adventure will be a little ... odd ... anyway, I can easily justify the loss of their changed, expanded (and somewhat weakened) lore uses as the end of it as being an aspect of the reality they found themselves in earlier rather than an innate change in them.  If it works out, then the change is permanent.

What do y'all think?