There is one more thing I would like to mention. I think it would be better to use instr instead of inst as an abbreviation for instruction, in both commands and source code. From what I have seen in the project, inst is also used for instance, whereas instr is primarily used for instruction.

Using instr in the source code sounds like a good idea because that's how dis does it. However, in gdb and lldb, I think they just use stepi and nexti for the LONG version and that kind of makes sense. I think I'll go with that - si and stepi, do not use stepinst or stepinstr.