I’m not disliking the idea of having a random character and having to stick with it for life. This however comes from the assumption that all character models are created equal, in terms of gameplay, which is just not the case.
Some models have a gameplay advantage and some players leave the game just because they do not like the character they have been assigned.
Characters of darker skin colour are, for example, harder to see at night and smaller characters have smaller hitboxes, which makes them harder to hit. This gives some players unfair advantages over others aswell as alienating players who have been given a bad hand and no way to fix it.
Also recognizing players at a distance across servers, while hard, is not impossible especially when you are playing in the same communities. This is disruptive because many players play vastly differently on different servers, being aggressive on some and friendly and social, maybe participating in RP on others, but the prejudice may carry over. Additionally some players will envy others just based on their given character model or treat them differently.
Currently, if I, for example, play on a given server with a friend, I already know how they will look like and they, in turn, will know how I look like without us ever meeting up on the map. This makes it near impossible (unless you roll the same character model) to try and impersonate others and run intrigue or socially engineer situations, which is, to me, a large aspect of these kind of sandbox games.
I think it would be wise to assign each player a new character on every server, every reset. Maybe even have the possibility to provide a “seed” for these player character assignments or maybe use the existing world seed for it. This would be especially beneficial to RP servers, as it would allow for roleplaying a more diverse cast of characters and not being stuck with one, forever, permanently.
In addition maybe you should assign each character a new name or pseudonym aswell, so people can trust that players not change their steam profile names to appear as somebody else also.
It would satisfy many upset players while not giving up on your initial ideas and beliefs and would also clearly separate different servers and worlds as different ecosystems where nobody can take other characters for granted.
The downside to this is that server administrators might reroll their seed until they start with character models they like, maybe even, since the logic would now be server side, develop mods or plugins to change your character model ingame and maybe even charge for it
Of course players are still able to choose the servers they play on and as such are not being forced to participate in such an environment.
On the other hand changing character models, if inconvenient, is already possible and used by many. People create new steam accounts and family share them to their main accounts just, so they get another chance at a character they like.
In summary this proposed change would apease many disgruntled players, while still holding up the gameplay over immersion concept and diverse population on servers and clearly separate worlds / lives on different servers and would provide more opportunity for RP servers, while also better balancing the game in general.