That's true, when you work at the bare metal level you can always fix things.
I've looked at CoCox and all the others, as far as I can tell you have to spend money to get C++ and a decent code size limit. There's always a gotcha like it doesn't work with my LPC Xpresso boards, doesn't support the LPC1227 or something.
I currently use the Code Red free IDE, only down side to that is that it's only C not C++ although I think you can get around that if you supply your own makefile for a project.
Rob