I still use Ratpoison. This looks interesting ; I like that people still actually make window managers. Probably a lot of creative work can be put into that.
Have you considered upgrading to stumpwm by the same author? It has all the features ratpoison does plus support for floating layout via gnew-float, among other things. And it's written in Common Lisp, so you can hack/customize/extend it as easily as [if not more so than] emacs.
