WARNING this document contains super debatable content that i wrote at 12:30 pm tired as hell
it is slightly revised but not really too much

If it were up to me the main levels would be rated as follows

Stars ranges:
    Easy 1-2 
    Normal 3-4
    Hard 5
    Harder 6-8
    Insane 9-10
    Demon 11-14

Stereo madness 2 stars ONLY BECause of triple spikes (without them it would be 1 star)
Back on track 1 star 
Polargeist 2 stars
Dry out 3 stars
Base after base 4 stars
Jumper 5 stars
xStep 6 stars 
Electroman adventures 6 stars
Blast processing 6 stars
Finger dash 6 stars
Can't let go 7 stars
Cycles 7 stars
Theory of Everything 7 stars
Geometrical dominator 8 stars
Dash 8 stars
Time Machine 9 stars
Clutterfunk 9 stars
Hexagon force 10 stars
Electrodynamix 11 stars
Clubstep 12 stars
TOE2 13 stars
Deadlocked 14 stars