Following on from earlier work, I've made available some AfterStep packages for Solaris.
Then, I tried some of the twm variants. I started with ctwm and vtwm, and then moved on to tvtwm and piewm. Then I hit a problem - piewm didn't work. It was choking somewhere in the lex parser, so refusing to load any config, so no menus or anything. It's based on a older version of tvtwm and, rather than attempt to learn lex and fix that, I had a go at simply adding the pie menu support to the latest version of tvtwm (tvtwm-pl11), and that turned out to be pretty easy.
So my merged source, boringly named ptvtwm, is available from here, as are the usual Solaris packages. The packages include piewm and tvtwm derived from ptvtwm, as well as ctwm and vtwm, along with a private copy of xli so that tvtwm/piewm can load a background picture.
That's quite a lot of Window managers, so I've put together a list of package window managers.
That's essentially it for now. I'm hoping to get Xfce packaged up, but there are a fair number of prerequisites that Solaris doesn't have (or has antiquated versions of) so the packages end up being pretty huge. I'll get there, but haven't yet got a build I'm happy to let out.