Well, I've decided, not only to make it less like LEGO Universe's famous Imagination, but also to open up more possibilities in the future (And make the Aura faction look really, really cool), to make Creativity usable in three ways. The first is the obvious direct manipulation, such as Creativity lightning, Creativity Spinjitzu (Ok, not really.), etc. The second is the also-obvious use of Creativity to create things using the LEGO parts we all know and love. The third... is the new one. Introducing the rune system. Basically, the idea is that a Minifigure's Creativity can be formed into symbols that can do various things. For example, someone might use a Shield rune to deflect an attack, a Send rune to send an object somewhere, etc. However, these runes often require an amount of Creativity that make them impractical for normal Minifigures who have not been trained or empowered. Due to being confusing as well, only those who have studied Runes are capable of using very many of them.
EDIT: Also, some runes are low-cost runes that will take the places EDIT2: some of the places occupied by quickbuilds in LU. And Message Obelisks erected by the Aura division will be used for sending mail.
EDIT2: Hmm, some LU-style quickbuild points will exist, actually, but they'll be... a bit different.
EDIT3: I've decided that players should only be able to use Runes for non-fighting, utility purposes, such as property teleportation. There probably won't be "rune creation points" and "transport runes" as I was originally imagining, and either modular rockets or "modular gliders" will be used.
---Yeah, that's the better part of my basic idea. I'll be editing pages to fit it soon.