There are so many good points here, I can only add a brief summary of my own personal experience. Your mileage may Will vary, of course.
I joined MD in a similar fashion. Maebius was mostly Me, Nate. I have the Hat, physically on my head when I played quite a lot. Yes, I filtered that through the lens of MagicDuel's realm and specific flavor, but I generally kept me as 'me' as if I were there in that place surrounded by folks and angien discussions and sundry.
Then, a while later, I wanted to try things in a different light. I created a Character of Gort Hedera, who had a sorta personality, (but was STILL really just a part of me I wanted to play with under the veil of internet-anonymity!) and had a lot of fun with it. I didn't really keep her identity a secret if people asked, but also tried to keep that character completely removed from Me. It was a mask I put on, and toyed with, when the mood struck.
Both characters (and the other minor very unplayed alts I have) were other experiments to test out a way of thinking, or viewing the world.
Both Maebius and Gort had value for their own unique reasons.
I have far too many alts, some to map out Story-mode paths, some to try a different personality play-acting, etc.
Different playstyle=different character. Most didn't work out beyond MP4, so sleep eternally now.
My suggestion, whenever I hear folks say something along the lines of "But I want to keep playing, yet I don't want to play XYZ" is to ask why you can't do both?
It's not exactly an either-or world here, it can be a both/and.
You may be judged by others, but really, the only REAL judge of whether it works or not is yourself.
Nothing wrong with trying. :)
Edit to add: in your specific case, I don't see why Change can't change. you say it may "require you to RP a complete 360" (which is a full circle back to where you started, fyi.) If it required a 180 degree flip-flop, well, there's always Mirror-symbolism. Balance, and whatnot. Cyclicity? Imagination? Nothing prevents that. Heck. Maebius even went rogue and killed people, which surprised a few folks. I got at least two "that's so out of character, what the heck?!" messages, but that was still "me", right?