I agree that the "community as a website" idea isn't exactly the best way to go, but I have already successfully integrated Dolphin into an existing website as a "community feature" without affecting the rest of the site and didn't really have any trouble. It's not that difficult to do, all you have to do is install Dolphin as a subdirectory in the main site and configure it properly.

I've even managed to integrate other software packages into the website and used Dolphin's see more member system as a "Single-signon" type system with a little bit of extra coding in the dolphin templates. (and without having to touch/alter the main Dolphin codebase)