I *think* what you're asking for is "use the same treatment for auras that we get in powers"... which was suggested a couple weeks back in so many words. 
Agreed though, some of the light-dark shifts are pretty neat.
Please read my FEAR/Portal/HalfLife Fan Fiction!
Repurposed
...and the virulent demands for lactose-rich beverages will follow.
>
Give a player the option for both "bright" and "dark" versions to many of their powers, and they will ask the same for their costume auras.
...or so shall I. Please?
(oh, and obligatory power pool/patron pool/ancillary pool plea here as well.)
<A note on the side comment above, BackAlleyBrawler, I did see your comment about Patrons not being as customizable as patrons, and I would highly recommend you rethink such a position, for the good of Paragon City. You have NO idea how fussy my villains would be if heroes could look snazzier than they. I hold no responsibility for the mayhem Paragon would have to endure.
That is all. Carry on.