Aww. I was reading your lists and saw that you had Aira on there. I think you should save Hyun-ji/Ji-hyun for your stage name when you and everybody else realizes that you're a famous singer.

I have a great one. Are you ready for it?

Sayuriiyairagornjihyun-chan101422.

Ohhhhhhhhh yeeeeeeaaaaahhhh!

I'm kidding, of course. And omg, Mizukaria sounds really pretty. It'd be funny if I leave it at that and then you tell me it means something ridiculous like "diarrhea" or "death rape" or "silly putty" in Japanese. O_O Silly putty! Gasp! The horror!

I agree most with the thing about it being possibly your only shot to change your name. Although your aforementioned sentimentality about it being your first name and such is attached to your current name, you could arrive at a better identity that you may feel expresses yourself and your art/activity on dA more than your current one (wow, I just checked and realized you yourself said something like this... but I'm going to leave it here anyway). You may also want to consider that once you become famous, you can have an interesting bit of trivia that goes something like, "Sayuragornjihyun-chan1014's previous username was aragorn1014 and was stated by herself to be her 'very first internet username EVER.'"