lately I've been finding some combo of the above to be enjoyable, and I think helpful
a few months ago, I started playing ghost with throwing balls out and running them
I could get through three and four pretty easily, then on five I'd run them about half the time
for a few weeks maybe a month now, I haven't been keeping track- just haven't felt like it
not great to gauge progress, I know, but I have been gauging progress in other ways
establishing a plan beforehand and focusing more on each shot has helped a lot
it's taken me years to get to this point, but I'm using more of the cb than I ever have
I'm considering different ball paths, I'm seeing what balls are going to do before I hit them
I seem to have more margin in my game- I'm still missing my spots, but not by as much
just the past few nights I've been stringing 6s 7s and 8s, playing loose, but with intent
not to say I don't still have issues- I do

but even those I'm getting better at identifying
anyway- if I were doing more focused drills, I might have picked this stuff up sooner
and I have done plenty of drills over time. but I'm of the mind that as bob suggests above
if one shows they care about what they're doing, stuff adds up.
ps, quality vs quantity, one thing I think has been working for me is actually playing less..
I would typically play 1-1.5hr.- lately I'm playing 45min.-1hr. now and getting more out of it