Hello Andrew,

You are rising a quest which is probably concerning most of the social network developers.
I agree that one of the biggest factor of the success of Facebook it's his simplicity. Google understood that very well too.

The key here is to keep everything as simple as possible. As some members have already pointed out here, there is no more room for too complex systems. A good example is MySpace.....the usability sucks incredibly. Not to mention the architecture and layout. No wonder see more it's dying out.

Actually if I would imagine a future for Dolphin, it would be something like a Wordpress eco-system. Incredibly simple and fully integrated with Facebook and other social networks.
It has a clean interface and you will never be able to break anything. Another strong feature is that it has his own community members which are able to shift from one site to the other thanks the use of Gravatars.

I think that if you apply the same logic to Dolphin, you could make it very successful.

Keep the good work.