Agreed, WPS can be slow and can really hurt development. I've used all of them, and I might recommend WebLogic for local use (since you can drag and drop EAR files in) but its a little risky. IBM has its own extensions and extras so it would depend on the external dependencies of the code and it might make integration difficult.
One thing that I've seen done in this situation is to use Eclipse plus build scripts. There's some overhead with the build scripts but they can be very valuable later on.
if i follow only those standards, and don't use those IBM's own special components like those fancy things in RAD, then i think ur suggestion is quite good. I also believe ant scripts are much greater than building from IDE.
as we use JSF in portlets, and using RAD can save lots of time. i am wondering whether there is a way to develop jsf porlets using RAD, but deploy to pluto or jetspeed.