(1) Enhance the FMP debugger to allow you to enter a logical expression (a conditional breakpoint) to break and debug from there. Say after n iterations of a loop or when a variable has a certain value. Currently you have to hack this behavior with IF statements.
(2) Possibly also a script step to raise an error so the current "Pause on Error" is more usable (configurable).
(3) Possibly also add a "Enter debugger If" script step as suggested by Siplus (a FMP guru on this site).