cgdb looks promising. I really, really liked the Turbo Debugger in the 90's. No debugger has offered me the same experience since. It was fast, the text-based windowed interface allowed efficiently jumping to assembly as well as to the source, view registers, editable hex dumps of memory, view watchpoints etc.

gdb is super-powerful but was a bit of a setback interface-wise because everything has to be done on a plain command line. And the GUI-based wrappers around it don't appeal to me much (don't know why, the ones I tried felt somewhat clunky).