Okay before you freak out , hear me out. Don't just come to comment without checking this OP (Original Post , not Overpowered *sigh*)
We spent a lot of time debating and making a kick ass banner for our house, and it kind of annoy me that anyone can use it even though we reserved a slot on the banner list. I see many EU using it, and now that we will put a banner based on our house, I'd be false representative for them to use it (I know , banner's are public, but ...).
What I suggest ...
If
you're not in a house, you can choose any of the many default banners OR you're forced to use Swadian Banner (which I'm against a little bit, if you want to play with your friends and look alike , but then again, you just have to start your own house). By using Swadian Banner, we then could tell who is in a house, and who isn't. (To be debated...)
If
you are in a house, whatever your character banner is using (in the edit char options) won't matter since you should be using your house banner (as if leaders would let some of his soldiers wearing different coat of arms or banner ? makes no sense...) This way , the time people put in making a nice banner is protected , random people can't use it , or fake to be in a house just because they wear the banner.
I don't think it would be a lot of coding if you include the textures of the custom made banners in a different banner file (so you leave all the default banners to be picked), but then again, maybe it does require some time and some code , but I think people who spent a lot of time working on a custom banner would appreciate that. It would also look cooler to be in a house and have a kick ass banner that others can't use cause they aren't in that house. Having 4-5 players from the same house sticking together will look much more RP and badass, then some other players using the same reserved banner and following them.
Discuss .. and stay respectful