Charlotte O'Sullivan-Tokugawa, my beloved, was my first ever character not just in SRP, but in minecraft RP as a whole. Infact, she even pre-dates that, being my first ever DND character and one of my first OCs. HOWEVER. Due to it being my first time in SRP, I was really unsure on how exactly to act. Thus, Charlotte's personality was almost one to one with mine, aside from the occasional comedic flare (i.e I would never touch a bottle of alcohol, but Charlotte was a frequent drinker).
I think it's actually kind of... Bad, to have a character who is too similar to you. Because if people grow to dislike that character, it feels like they don't like you. It was partly for that reason that I actually grew to dislike Charlotte. Although our personalities had separated, I still saw a lot of myself in her which wasn't ideal because she was disliked by the majority. I didn't want her angsty self to be a reflection of me who is quite the opposite. Though looking back, there were definitely some stark differences between me and my character.
With regards to other characters, it is very different. Charlotte was the only one I actually dedicated myself properly to. Fuyumi, Suzuka, Anko, and Shoko were never really played out to their full potential. Fuyumi and Suzuka were simply characters I had for the sake of being involved in the clubs I loved (still miss you photography club). I never really gave them a set personality, and so therefore there was a LOT of character bleed. Fortunately, I only ever played them when I was in a good mood, so to people who don't know me very well Fuyumi and Suzuka just seemed generally happy.
Nowadays I don't really play SRP that much anymore. This has lead my current character, Shoko, to act how I view the server. She is much more laid back, calmer, and of course, actually minds her business. I think if I do become super active on SRP again, I will try my best to keep her this way. It makes rp much more relaxing, even if it does sacrifice a bit of sustenance.