YER is unironically my favourite knife

Persian Persuader Demo Knight. It is less consistent but boy does it feel great to get that streak of charging from enemy to enemy and having cleared the entire back of the enemy team.

from what I've seen the red tape recorder is probably technically a direct upgrade in MVM? acts like a normal sapper on the robots, however I assume it'd have a much more useful effect on the robot engineer sentries which usually have a massive healthpool which makes the normal sapper do just about nothing to the sentries

for medic, if you want to be less useful as a medic but more independent, try the Blutsauger (health on hit), Kritzkrieg, and Amputator. The taunts with Kritzkrieg and Amputator both heal yourself. Solemn vow if you want to know if you can take that enemy on.