Random crits are too random, thats what gives them a problem. Its not fun facing a crit rocket from a non skilled person. And from a skilled person, even if it happens it feels like its unneeded. This is a major reason that they should be removed.
But i also like a randomness factor in pubs. Not everything should be as predictable as comp would. so on that having some random crits are fine. Now valve has such system that makes them less random where performing well increases the chance. But this is more favoured to the good team. This used to be good as tf2 had alot of stalemates, it allowed rounds to randomly happen by that small boost.
But the current tf2 many times has the opposite (unless sentry stacking - but thats an issue on its own). Teams are that bad that defenses are entirely lacking and often rounds end up fast. Now if this could be solved with random crits it would surely help. But it wouldnt. Fast deaths are counter productive to creating stalemates (the 'balanced' situation).
So on that, removing random crits is a good thing. They are heavily outdated. But i still would like to see some alternative thing that is acceptable for pubs. For example: When a team is facing alot of deaths in a short moment at a ratio of 5d1k then the team getting battered should get some defensive boost. This could be random crits to allow fast deaths, but again, this allows a too fast change which isnt good. So on this a defensive buff (ie. the entire team recieves 20% less damage) could do much better.