Essential block: (target do every day without fail)
15 minutes of One Move to Live problems from 1001 L&D or Beginner problems from wBaduk or Beginner Problems from Tsumego Master
15 minutes of One Move to Kill problems from 1001 L&D or Easy Life and Death Problems from EasyGo or Beginner Problems from Tsumego Master
Preferred addition: (try to do every day if possible)
15 minutes of Three Moves to Kill problems from 1001 L&D or Pre-Intermediate (Easy) problems from wBaduk or Medium Life and Death problems from EasyGo
15 minutes of Tesuji problems from EasyGo (easier ones), tesuji problems from Goproblems.com or Get Strong at Tesuji (when I get it).
15 minutes of Basics Problems from EasyGo.
15 minutes of Three Moves to Live from 1001 L&D or 15-12k problems in SmartGo Kifu/Goproblems.com
For when I'm feeling good and want to push myself: (try to do but not worry if not done)
15 minutes of 501 Opening Problems or fuseki problems from goproblems.com 20k-12k level.
15 minutes of Graded Go Problems for Beginners 3 or Pre-Intermediate (Easy) from wBaduk or Medium Life and Death from EasyGo.
I think there's a good enough mix there to keep me from getting bored with any one set of problems or style of problem.
Reading: (Optional compared to the essential tsumego section above)
15 minutes of Tesuji by Davies
15 minutes of Opening Theory made Easy (reread because I really do need to reread it)
So, on a good day 2.5 hours of study, on an off day, a half hour of study. I think this is doable and achieveable and allows for dips in mood/concentration/kids getting sick/whatever. Broken into 15 minute blocks because I find this easy enough to concentrate for and motivate myself to do. Obviously I'll have to update this list as I get new problem sets and/or finish a problem set multiple times and need to retire it for a while lest I start memorising it. I feel a lot more motivated now that I've set out specific targets.