utf8mb4 unicode 520_ci
From my understanding uft8mb4 would be good for character with mutli language (character) support (japanese for example). uf8 only supports 3 bytes while uf8mb4 supports 4 bytes. So it sound like the obvious choice would be uf8mb4, but the catch seems to be that you have a length limit (Damn it! I want my cake and eat it too), which is a little concern (I think).
Then you take into account about the 520 standard; which offers more, from what little I could find on it. But that is of course the issue, I could find very little about it. Only that people say it's an improvement, yet being very vague on how that is.
So being that I do want to learn and I do want the most I can get with as few restrictions as possible... I figured someone here may know a thing or two.