I am in the midst of restructuring my GoodTask layout to hopefully make it more useful. I have switched to just two key lists, work and personal and am doing everything else through smart lists. I'm curious of what smart lists people find most useful. Currently I have ones like:
Waiting on... and Discuss With... both sorted by tag
I am also working of ones based on time/energy on the order of quick, focused and deep dive, but I haven't quite worked out the right setup for those yet.
Finally I have Upcoming for scheduled tasks. I had several but by switching the view from day to week, etc. to allow me to have just one.