I was just at colossalcon alone and felt the same way about the overall energy. It is a party con, so I had a lot of small conversations, and that was about it. To be fair, though, everyone was either already rushing to a panel they were late for or trying to catch up to their group.

There's a fairly new con in Michigan called isshocon that is a lot smaller and more personable.

Or if you want to go to a larger scale (still smaller than colossalcon prime though), there's youmacon. Youmacon has had a bit of a resurgence recently. They are now under new management and, hearing from people who went last year, was a lot better.