I know what you mean. I hate that head-void feeling I get when there is no next trip on the calendar.
I did a two night trip down the Baskahegan a few years ago with some friends, finished in Danforth. It's a nice river and hardly anyone has even heard of it. Our trip was Memorial Day weekend and we saw nobody on the river, and only a couple fishing boats on the big lake. In summer I think the locals party on the lake campsites, but I doubt the river is ever crowded.