As @Folke has eloquently pointed out in several threads in the help area, one of the main missing features from other apps (nirvana, zendone etc.) is a way to highlight ("star") a task for immediate focus without turning it into a scheduled task that is moved onto the today list and removed from the original e.g. Next list.

I couldn't handle working with the Today list as a focus list - I really tried, but it renders my Next list useless, removing the option to view the tasks I marked for immediate focus in the context of the tasks I haven't marked yet and make adjustments to account for changing circumstances.

FWIW, I am using High Priority as my Focus marker now. It significantly increases the effort and time in marking the tasks - but at least I am left with a functional Next list when I need it as well as a "Focus only" view - via a Filter.

I really hope they come up with a better way - but for now, this sort of works.