I’d probably use the debugger more if it was standalone/usable from the command line. But in practice the only thing it does that really seems useful is the ability to set breakpoints and step through execution, and so I end up faking them with my own roll-your-own debugging methods.
If T3 had a debugger like gdb and a memory profiler like valgrind that would be very cool, but I’m probably one of like 1% of the already tiny T3 user base that cares about that kind of thing.