How to get better at guitar hero?

now this isn't just the basics... I have been playing for a while now... not religiously but i'm pretty good. I can do the the intro solo to rush's spirit of the radio 100% and can do knights of cydonia, cult of personality, raining blood (3 star), one by metallica (5 star), finished the satch boogie barely a handful of times (really hard) but yeah so that gives a general idea how far along i am... I just found that lately i've been at a standstill for too long any ideas how i am to progress anymore? i mean i am pretty good and can beat mostly anyone i know but i know i can do better but dont know how to get there... I play real guitar too and know it takes time but it's been a while i've been waiting and the proress is so small i can't really beat my old scores from months and months ago