Does anyone else think that Trent's 9 obsession thing was based off of John Lennon?

That was my first thought as well.
There's tons of other odd coincidences... the Beatles, and there's what guitarist Jimi Hendrix did write before he died...

"There, the musician drew the number nine, nine times, and 発言しました 'nine consciousness was the highest form of consciousness'"

He took nine sleeping pills and ended up dead the 次 morning...
I totally had found others, too... but I can't remember a lot of em now. Case and point, there's definately connections between Trent and other famous musicians.

Based on what MadiYash said, I think that they wanted to make Trent like a famous guitarist.