Conventional wisdom says that it's best to keep a pet's name short, though I have not always followed that. I don't believe in talking to them in short commands, either, which some advocate.
I have heard the theory that cats respond best to names with sibilants in them ('s' sounds), and have tried to do that or something close to it. We didn't have any choice with Gryphon (though the 'ph' does come close) or Nibs. But the cats I (or we) have named ourselves have been Chinook, Percy, Shasta, Suzy, Samantha, Cindy and Fawn.
Chinook and Percy weren't in my life long enough for me to be able to comment on the success of their names. Shasta knew hers and (mostly) responded, Suzy responds well enough for it to be obvious she does know her name, but it's completely on her terms. Sam was pretty good, Cindy definitely knows and responds to hers -- again, mostly. Fawn is the least responsive to her name. I think she does know it, but she just doesn't give a hoot.
They've all had numerous nicknames, though, too, some of them quite unrelated to the given name in sound, and respond as well to them.
Gryph and Nibs did respond to their names pretty well, though, interestingly, it wasn't until they had been with us for a while that they did. My theory on that is that their previous human referred to them as "the lads", and I hunch she didn't actually call them by their names all that much. We use our kids names all the time, especially when we're getting acquainted. I hunch that that is more important than what the name sounds like.