Agreed. I personally like spending a day at work just going through and knocking out all of the small bugs left on a project that was deemed ok to launch with so we could focus development on the larger issues. Best way to provide great customer support for post-launch.
AdminCP and the log-in for AdminCP was designed to be isolated away from your forum. This is so that if you're forum isn't working at all.... ie.... A nice blank white page for example or random code ..... You could still reach /admin/ and attempt to resolve it.
It was also designed to be basic... ie.... As close to html / css basic as possible. For browser and device compatibility (as well as server side compatibility).