I've only read T'Ryssa Chen in a few things. I think all I've read that had her in them were the Cold Equations trilogy, the first Destiny book (I never did read the other books in that trilogy) and the TNG parts of Typhoon Pact and The Fall, and honestly she wasn't particularly memorable in most of the ones I've read with her (I loved the Cold Equations trilogy, but I didn't even remember she made an appearance in any of the books until I looked it up). She seems just to be there to have a nontraditional personality in the book (well, that and the TNG book crew had only about half of the TV show cast left, so they probably needed more characters). She's not really interesting, and seems just to be mostly there for shock value (which is pretty lame), but I don't dislike her. I just don't care. She's not a bad character, she's just not a good one. She could easily be erased and not effect anything, but it doesn't bother me if she keeps appearing.
If she became the focus of a book I might cross the line from not caring to being semi-annoyed by the character, but as long as she gets about as much time as she has in the books I've read, she's not a big deal. Kind of like every other TNG book supporting character that's there just to make up for about half the TV cast not being on the Enterprise anymore. Don't get me wrong, I'm enjoying almost all of the newer ST books I've read set in the current continuity, but the Enterprise-E books do lack a bit in the crew department. Then again, its still got a better crew than Titan, so there's that.