depends on the mc most of them are stupid so i use the default name but sometimes i do relate with a character and its easier to see it as myself on the other end tho sometimes i like the mc enough to keep their name like in desert stalker i use the default name zaton or whatever cause it fits the setting
Mostly I go with what the developer intended for the story and maybe changing some little things on the flow. I got enough phantasy in me to make it work either way
I try to play as myself, with a health dose of 'this is not real' as I would never do the risky stuff most MCs do. But, I can't play dark games as I feel awful making those types of choices. Always love root vs corruption route. It is a fantasy/story so some gaming it out is OK.
It really depends on the vibe of the game. While I don't exactly self-insert, I do make a lot of decisions as if I were the one making them in real life, but only if the character backstory implies they are at least somewhat like me. For example, I've never been interested in banging my sister or mom IRL but in a game focused around incest, I totally make that decision in the game, so there are obviously exceptions. I also would never rape, extort sex from, or blackmail a woman into sex, but if that's the type of game I'm playing, I'm making that choice every time.