I'm on a roll today. I just beat my first Level 90+ Dark Note. I decided even though I didn't have any healing magic equipped (since it generally isn't good for crystals), I'd try my new Level 99 Dark Note. I got Battle at the Big Bridge and managed to get an S rank on it without needing to use my Hi-Potion. Unfortunately, Boss 3 dropped a Mog's Amulet instead of a Crystal Fragment, but it was still an awesome experience to clear the note.
I've unlocked about half the extra characters so far.
Most I had was 5k or something once. I think I may get a high level dark note since I have 4 characters at 96+, but I'm scared I'm gonna do bad >_>
When I started this game, I was rather horrible at it and all rhythm games. When I got to the point of first trying Level 90+ Dark Notes, I was much better than I was when I started, but I still solidly failed the dark note. Now, my skills would truly surprise the September 2012 version of me. I have faith you can get to that point of surprising yourself too.
There may still be people way better than you, and there may still be people just as good as you who've invested a mere fraction of your time into the game. But as long as you have a trend of improvement on yourself, you'll get to your trophy/character goals.
I've been playing a bunch of Dark Notes today and still haven't passed 19335, but I've mostly been focusing on the Level 99 Dark Notes. In the meantime, the game seems to have forgotten to occasionally reward me crystals when I beat boss 3. -_- I keep getting the 3rd item (a non-crystal) whenever I beat a Level 99 Dark Note. I'm also trying to run into Chaos but haven't found him here yet.