It's easier to create several small tools
than one huge program. And it's easier to debug and easier to maintain.
You will get the project to a usable state quicker, and it would be
easier to extend it with new tools later on.
I am not a Java fan either (nor C for that matter) but IDEA is a good
IDE.
Whether you decide to branch QED or just develop it, the older versions
of QED will remain and there are other editors.
A set of tools would have to be well integrated to work well.
Are there any open source IDE projects we could borrow from ?
IDEA has loads of features, many of which I never use but here are some
of the basic features I like and rely on, in no particular order.
Editor
* can jump from a variable/function use to it's definition
* can search code for usages of a function/object
* can see changed modules and which lines and rollback individual changes
CVS
* can compare local code with CVS rep
* can merge bits of code from CVS into local version
* easy to CVS update/commit/checkout/rollback
Debug
* easily set breakpoints in code
* can ignore breakpoints without having to remove them
* jump from errors to code
* can see all variable in scope and values