I agree that we need variety, for a variety of reasons. I listen to and love stuff from Smetna to Scruggs, I like to play at blues, country, jazz, funk, and some rock (actually lots). I never developed and ear for metal, or whatever is the source of those annoying thumps emitting from some cars. And learning is a mystery, for me at least. Otherwise why wouldn't it work the same all the time?
Consistency keeps the wheels on things for me. Every possible day I sit and run the same routine, with a metronome, for around 20 minutes. (These are my bad habits folks) I run the 5 boxes, in G, up and down at least a few times, at 4 speed settings from 50 to 80. Then I step through the little chord shapes for the 7ths. this is all Griff stuff, not the way he means it to be used for sure. I don't do this to get better, I do it so I have a chance to play. This time assures that my fingers will move when and where they are needed, helps maintain my fingertips, helps with ear training, and just kinda "keeps me in the saddle" so to speak.
This is like a "no goal" time. No pressure. I put in the time. On a good day I can daydream, or problem solve if you wish, and hear the patterns run in the background. (loose the concentration-connection and crash hard - start over
) Anyway, this is how I stay in the game with my instruments, and my peace of mind. Since my goal is totally achievable, just sit and do it, I don' have to decide. How I feel, what's going on, none of that matters. I will eek out a few minutes to spend with one of my friends. If that helps me get better, fine. Sorta Zen time.
I also just sit and play, if I can...time and all getting in the way. And now with an amazing amount of coaching I try to record and play vjr, wow.
Now, if I just worked on learning I'd be crazy as hell in no time. I put too much pressure on myself.
If the solution was as easy as buying a guitar, or tossing one out the window, that wouldn't be any fun!