After sleeping on it, I think I'm going to switch hosts and try to keep going with SBCL and Hunchentoot.
If you're reading this and you know of a VPS unmanaged web host that's known to work well with SBCL, could you please comment and let me know what host you use, and what plan at that host, if it offers more than one plan, and what OS you prefer? So far I've heard Slicehost and OCS Solutions suggested. (Slicehost offers Gentoo. Do I dare?)
Note to all, my current host for my SBCL-driven site is FutureHosting. I'd advise people to avoid them if you plan to run SBCL. Their support and service is usually pretty good as long as you don't push it too far, but their servers are pretty wonky at times and after the comments from my last post, I wouldn't be surprised if a lot of my problems were due to some kind of VPS misconfiguration. Their support staff told me nothing more than "pay for more RAM" when I informed them of the problems I was having.