Ability to use ANY item on craftland as part of the design on your cape. This of course would exclude blocks and vanilla items used for designs already. But what we could do is make it so that if you wish to use the Item texture as a design that it has to be crafted in the loom.
Example: Make your normal banner and continue doing the normal stuff in normal crafting bench. All recipes involving items will function normally. Let say I wish to use the golden apple as a design itself rather than making a Mojang Symbol. I could go to the loom and craft that step within the loom.
Might just be over complicating things there but who knows.
But the concept is just to be able to use any Item as a design on the cape. The item would be grey scaled when applied to the cape and colored depending on the dyes used. This would open millions of more designs.