If you're writing fiction, you can name people anything you want to. You get to pick! So, unless you have a very good reason to, choose names that are easy to read, easy to say, and easy to write.
Too often I see people picking names that they like, without considering the reader, or even their own work.
Arghein'davaerious might sound exotic, but how is that actually said?
(Note, I just made that name up. Similarities to anyone's work is unintentional.)
There's a ton of problems with that name, not as a name, but as a word chosen by the writer.
How is the “gh” said? And how is ghein said? How is the apostrophe said after the “in” or “ein”? How is the “er” or “ious” or “aerious” said?
Forcing your reader to decipher anything is usually bad. And I even used rather straight forward spelling. If I start replacing letters or throwing in stray “h”s and “y”s, it becomes a nightmare.
Go buy yourself a baby name book, find one that tells you the origin of the name, or sorts then by language and region. That'll lend cohesiveness to the names.
You can change them a little if you like, but it might be good to have a couple friends see if they can pronounce your changes before you submit anything like Khys-tougih'jhoffa. (Eh? Guess what that says. I'll tell you if you're correct.)
Also. Double also. Avoid style rules that upset people. (I'll write more on style later.) If you can pick James or Jesse, please, avoid the ES ending. Because, while most of us were taught in high school and college to use James' for James possessive, there aren't real “rules” for these things, and some people prefer one form over the other.
(Also, I once stopped read a story because there were a pair of characters named James and I couldn't decipher what the author was talking about.)
Strunk and White, for example, recommend the 's (resulting in James's, Jesus's, and Alli Baba's) for any singular possessive. And while some people's brain alarms are certainly ringing right now, I feel it safe to claim that the Elements of Style is more of an authority than you, your high school teacher, or your college professor.
Assuming none of these are world renowned editors or grammar geniuses of course. If one or all of these is world known, feel free to cite the well circulated style guide as comparison.
Professional productions almost certainly use a style guide, so use their preference. Otherwise, you get to pick.
If you're a freelancer writer, you're likely to be subjected to the style guide preferences of anywhere you submit your work. If they like the opposite of what you used, do you really want to go through and change them all?
Save yourself the headache and name your characters things like Alexander Shaw or Xjian Moliko.
(Yes, people might not know how to say the Xji, but that's only one stumbling block, and certainly no one is forcing you to use east asian names.)