"... installing a lot ..." If you're installing in businesses, I would suggest either SBS Essentials (same platform with some nice-to-haves for a small or micro business) or waiting for a Storage Server Essentials box to hit the market...
As for workarounds:
- Set up a virtual machine.
- Take a snapshot just before joining to the server.
- Join to the server and finish server setup.
- Revert when done.
Or do what Microsoft intends, which is deliver the server in "ready to finish" state, i.e. OS installed but configuration not completed and no joined clients. Then join a client belonging to your, umm, "client". :)
I'm not on the WHS team, I just post a lot. :)