"Test xxx" VMs: suggestions to add more environments

Builders

I see we have:
*ReactOS: "Test KVM", "Test VBox" and "Test VMW".
*Windows S2003: "Test WHS".

Would it be worthwhile to have some other VMs?
Like:
*Linux + Wine: we import/modify/create "Wine" (code and) tests.
\ (Obviously some (km)tests would be skipped there.)
*Windows XP: some testers(++) (still) use it.
\ (We don't care some tests do not succeed, but none should crash (the OS).)
*Windows (7) + Virtual PC: some testers use it.
\ But mind CORE-8724.
*(Emulators like) Bochs, PCem (v12): some testers use them.
\ But they may be too slow?

These are all environments that I saw used (as a cause or comparison) in issues.
Wine seems the most interesting, less than but in a similar way to WS2003.
WXP would be a help to support (some) community people who can't/don't have WS2003.
The others ("virt/emul") are probably just (would be) nice to have.

NB:
If we are short on IT resources, these new VMs (and WHS too, I think) could run less often/priority...