Another option, and one that I used to use is to connect the amiga native display (ie. aga) through a tv tuner card thats plugged into a pci busboard. This will give you the best of both worlds. The far superior output of an rtg display for system frindly stuff and the os itself, plus being able to use custom chipset software (using same monitor).
Personally though Id upgrade your cpu 1st though. While there's definately benefits from going rtg, even on an '030 the cpu will hold back the amount of benefit.