There seems to be quite a few things on the Internet about good Alter self forms for humanoids, aberrations, outsiders etc., but, surprisingly given that Necropolitan is a pretty good option for Wizards, no kind of discussion whatsoever on good Alter Self forms for undead.
So, what do you guys think?
As an interesting sidenote: Alter Self doesn't have the clause from Polymorph that you can't turn into an incorporeal creature, although you don't gain the incorporeal subtype and all the nice things that come with it.