Small replicating probes at high fraction of C sound good on paper. In reality, there is interstellar matter that can destroy your high-fraction-C small probes

Small replicating probes at high fraction of C sound good on paper. In reality, there is interstellar matter that can destroy your high-fraction-C small probes when colliding. Space radiation will deteriorate their condition as well. Do yourself a favor and educate yourself about space radiation. It's really bad in the interstellar space. Even your favorite AI creatures need protection from it.