1. Unless they're speedposting, metag-gaming or just doing something intentionally disruptive, I don't really consider if 'fair' to judge a character because of their attitude. You want a self-centered, egomaniac? That's fine. You want someone who believes they deserve all of the sensei's attention and special training? Try that shit. I can tell you right now, people whom are self-centered in person find even more obstacles than if they weren't. Just recently, I covered a shift due to two employees being fired. Normally, I'm management. This time, I was regular crew. One of the new trainee managers thought she would make the entire evening about her and her 'accomplishments running floor' due to the high sale count after I basically kept our grill and back window in line while she gossiped in the front. She tried to brag to our bosses, but she was essentially scoffed at. When she asked for more training in floor to pass her evaluations, she was denied and given the same amount of time as the other trainees. The difference here is that now a majority of the crew dislike her due to her attempt to take the glory for passing sale counts for three consecutive hours without even rewarding or meriting the crew. Situations like that, albeit even worse, will happen in a roleplay. If you're in a D&D as some badass mageblade that thinks they can solo the boss, you might not get heals from the Priest you pissed off after the last meeting. You might die. That's extreme, but an example of the consequences. In any case, I see no reason to bitch about or eliminate those characters. They exist in real life and I personally like having them here and there in a game, if they're roleplayed correctly - and that might actually take a few acts from a GM to intentionally berate their ego.
2, This is really similar to the first, but in this case, I find it more rare. However, if a person wants to play an introvert or an unsocial character, fine. Back when I roleplayed under mentors, I remember my personal mentor had this one pet roleplayer. She only had a handful of character concepts, but she did them well. Very well. One of them, the one we all became quite acquainted with, rarely said anything, and most of the time she spoke it was "Fucking idiot" or something along those lines. Those are character types. Those are valid archetypes. That's personal preference and it's really a dick move to just hate on personal preference.
However, I do see a common trend here, and that is lack of interaction. If roleplayers just aren't interacting, they might just be poor writers. I know you can interact with unsocial characters and narcissists easily. Back from the 2. point, I created a dynamic with a very prominent, recurring character of mine that repeatedly and intentionally hit on the female RPC because, well, it was funny as hell to see an unsocial character be forced to interact in such an awkward way with a character that everyone knew as a half-assed, likeable rebel that was just powerful enough not to get killed by the female, whom notably had what I called "brown-nose power", but whatever. We even ultimately created a very, very interesting and in my opinion fun to play Fruedian trio in the sense that my character was the Id, the female character the Superego and there was another female character and roleplayer later on that became an unrequited love interest of the other female character and acted as the ego. If you consider it from this aspect, there was extremely humorous exchanges where my character would flirt with one of them, get either no response or an awkward one and then intentionally go to the other and one up his game as if he was competing with himself, all just to irritate the originally unsociable female because of her crush. The dynamics and interaction here is endless and quite entertainin.
3. Now, this is a type of roleplay. Actually, it's a type of roleplay common with beginner DM's in D&D and tabletops. Sometimes, to develop a plot, it's just less freeform. Some people actually like roleplaying as a PRECREATED character where a Moderator has fleshed out what's going to happen, and the roleplayers use skill and literary technique to jumble it up some. I actually enjoy these myself, if they're done right and especially if the Moderator is fun with it. You might not like it, but it's just a different flavor.
I'd have to see the individual instances these occurred, but a lot of this just seems like bitching about styles you dislike. If there is anything I personally dislike to a great degree, it's feminazis. One time, I tried to roleplay on a forum full of nothing but raging female (possibly, not too for sure) writers with a lot of androgyny and sexual tension in their lives. Lemme tell ya. I lasted a fewwwwwwww days before being banned, and I shit you not, I was banned not because I broke any formal rule, but because I didn't ask permission to post in the personal forums of each "Leader" of the "Kingdoms" after I had gained approval to create, of all things, a traveling circus. They literally just found a reason to kick me out, and I had under fifty posts, none of which were anywhere NEAR as bad as what I've posted in this thread alone. Point being, what you see here is nowhere near as bad as it gets for clashing personal preferences and you might just need to get used to it.