I think what would be good, is not a RAD tool, but a general C++ Editing environment inside Lazarus. With simple project management, the ability to spawn your make of choice (Make/Jame/Ant/etc) and to track through the output, with a nice built in gui interface to you GDB back end of choice. Then you have 1 environment for all your programming needs. For example Load a C/C++ Project and the Window builders disappear, and it looks like a good C/C++ IDE.
Use C/C++ for embedded or system programming, and FPC/Lazarus RAD for your GUI programs. Best of both worlds. I think C++ isnt a very good RAD language anyway, cuse it isnt structured enough. RAD doesnt mean OO, so dont flame me. A good RAD langauge in my opinion should be simple, clear and unambiguous, pascal does the trick, and removes a lot of the pitfalls of C derived languages. From my experience, it is more rapid to write a working Pascal program than a working C/C++ Program.
Anyway, thats my 2c