I think the future is to have a wallet with multiple templates/themes or multiple wallets with different GUI. The more options we have the better.

I agree, a modular design or one that offers a flexible and easy to use way to customize their UI to their needs / preferences is probably where the roadmap should head.

Defining the target audience(s) is still the first step. Once that is done it becomes possible to come up with designs to meet the needs of that demographic, or design common UI elements (modules, plugins, novice/expert modes) for various audience segments.

The brain-trust for BitShares UI is primarily @svk, with @cass contributing graphics and his UI experience. I think there are others who have contributed as well, don't mean to slight their contributions, but svk & cass are key contributors.