To be fair, I mostly threw this one in for the sake of completeness. I won’t claim I’ve had much success with the min6, though I did enjoy the root-5 variation that looks like an ‘M,’ as it is easily dropped to a minor add-b13 chord that I’d never played before. I also found that this chord works much better for me in arpeggio form. Sounding the notes individually scales the heavy dissonance back to a more usable tension, a strategy I plan to test further in other chords I’ve had trouble using.
The major sixth is another chord that feels more jazz than rock or pop, but you don’t have to look too hard to find it in use. Lenny by Stevie Ray Vaughn and Sun King by The Beatles are the best two rock/blues examples of a major 6th chord that I came across.
Another chord that isn’t the easiest to use in a rock context but shows up frequently in jazz. Also referred to as the half-diminished.