There are two things I'd like to mention here as I've been reading through the issues (opened and closed).
I'd like to propose:

1. toggle for range and movement check

• this way the conflict with gray'ing out OOR abilities is almost solved
• rotation itself becomes much simpler and predictive ability icon becomes much simpler to do as there are less conditions to check

2. toggle for always-on display: OOC, no target, moving, ...

• if 1. is implemented, it's also possible to display the suggested ability 'always' ex. when flying - not checking for moving, not checking wethere as there is a target
• suggestion here: assume it's single target skill to simplify things

I'd very much like to here your feedback about my ideas. Thanks!