random crits have a large amount of hidden or visible benefits for gameplay and actually aren't all that bad.

that's just wrong.

Random crits make memorable moments.

No.

Random crit kills encourage new players.

You should be encouraged to get better at TF2 by actually getting better at TF2. Not stumbling into kills that were only given to you at random.

Random crits make melees used more often.

What does this have to do with anything? Primary and secondary weapons are primary and secondary weapons for a reason. Also, random crits ruin melee fights where maybe two demos are trying to bottle each other to death. One will just "oops" into the other and wins. Ruins the fun :(

Random crits make fights more unpredictable.

TF2 pubs have plenty of chaos already. People act like random crits going away means no more Kritzkreig or other unlocks that can create plenty of chaos on their own.

Random crits give a useful balancing tool.

This is just wrong. Nothing should be balanced around crits.

Random crit kills allow for stalemate-breaking killing sprees.

....Ubercharge?

Props for trying to play devil's advocate, but I just really can't understand defending them.