I notice that both in the OP and the comments that the biggest complaints involve how the bass fits in the mix. I feel this curse more than most. I don't like to segregate music into genres too much, and just want to hear what sounds the best, and I like a LOT of bass! Film music sounds good because the bass is vast and deep; P-Funk and the Beatles sound best when the bass lines are loud and clear.
Meanwhile I play a lot of loud aggressive music which I love, but I hate the "tried-and-true"/wrong way of doing things. Specifically, "the bass can't be up in the mix in metal." (even though a guy with an 8-string guitar will gladly tune down an octave below normal and put it up in the mix)
I learned from classical and choral music that there is a correct formula for acoustics. Picture a layer cake. The fattest layer at the bottom (width = volume) should be your bass frequencies. The middle layer is where the mids go, and the thinnest layer at the top is where your treble instruments go like tenor vocals, violins, guitar solos, etc. The frosting is stuff like piccolos and chimes that will still be audible even when quiet. The principle is to cater the sound towards what humans will easily discern, and listeners will be able to hear the treble instruments even when not as loud in the mix. Bury a bass and all you have is a sound that is felt but not heard.
