When it comes to homework on the violin, I've got enough to last a lifetime. Here are the things that needle me about my personal abilities. Whining commences... now:
Intonation - Why does it sound great when I'm on the G and D strings, but wretched on the E string? Why can't I ever get that octave to sound good when playing a double stop on the A and E strings?
Bow - After 21 years, you'd think I'd be able to bow straight. In fact, at one time, I did. I still don't know where things got cock-eyed. I think I joked recently that everything got bent after I went off to college. I'm willing to bet that my bow grip/hand position is still wrong. My violin teacher in college told me I was doing it all wrong.
Bow Strokes - I've never had a smooth sound. It always has had a slightly crunchy, organic feel to it. Add to that the difficulty I've found in getting that finesse in performing certain bow techniques. Collé, ricochet, sautillé. Lots of fancy names. The latter makes me want to cry. I've never mastered it. Too bad it's a key bow stroke used in a piece I'd really love to perform in public some day.
Finger Dexterity - My fingers on my left hand feel like they have a speech impediment. I have the worst time getting them to move precisely. I'm familiar with the myriad of exercises that exist to help one nail a fast section of music, but by gosh, I still usually end up feeling like my fingers are drooling all over the neck of my instrument.
General Limberness - My posture, stance, and grip have a certain tightness. I'm not a terribly relaxed performer. It's practically a guarantee that my left hand will look like it's gnarled with arthritis from the way I contort it in an attempt to cover all the strings I need. Most of my bowing problems hinge on this tightness issue as well. Maybe I just need a good masseuse. Volunteers?
Personal Practice Habits - I don't really get off on practicing scales, no matter how essential they are for becoming a good performer. So I don't. I will work on etudes and other studies, but I often toss those off the music stand for something much sexier. My lack of practicing during high school and college, and then beyond has led to a lot of unproductive moments spent with my violin. And when there isn't proper foreplay, you know what happens. You're never quite satisfied.
So I've got a lot of homework if I want to improve. I'm actually looking forward to attempting this.