A new guitar won't help you improve. It's perfectly fine to want a new guitar but don't try to tell yourself you 'need' it. If you think your tele sounds too thin then you probably just want something with a humbucker. So if you feel like that's something you really 'need' then realize you could get something cheaper. Guitarists in general are overly obsessed with equipment, 99% of your sound comes from your hands.
But if you want it, then fug it, get it.
- SOJA PIE'd this