Yeah KISS engineering... i like that

But you didn't answer my previous questions

Anyways, a serial communication, a LCD do the job as well and don't require any Bootloader (even if pretty handy) or ICD. Nobody work the same way. I don't use ICD really often. few times a year or so.

Any ICD will be slow, so you may need to enclose some part of your code with ENABLE DEBUG and DISABLE DEBUG.