hmm your "blank" way seems like a good but cumbersome idea.
i can't say that ive tried it but here's what i suggest:
*go to the apps folder and duplcate a small app (like bossprefs or something)
*delete the "icon.png" from the app folder
*if you have app-names displayed (you can just plain turn them off in SMBprefs) then you'll need to go into the strings file and delete the name string
*duplicate your new app as many times as you want spaces
there's something else that might work which i noticed once:
* install heaps of apps you don't want from installer.app, then position them where you want spaces
* uninstall those apps through installer.app
* hey pronto - gaps! (just dont try respositioning things now)
hope that helps
doobs