There's also loads of stuff installed into /System, like support frameworks for Project Builder and debugging versions of the libraries.
I haven't tried it, but for each of the Dev packages in /Library/Receipts, you should be able to do something along the lines of:
sudo lsbom -s /Library/Receipts/DevTools.pkg/Contents/Resources/DevTools.bom | xargs rm -f
Do this for DevDocumentation.pkg DevExamples.pkg DevPBWO.pkg (if it exists) and DevSDK.pkg
Of course, piping things like that to rm is always dangerous. It's untested and could toast your HD. You should really be sure you want to install things like the Developer Tools
