Everything obviously depends upon when football can be safely played and, relevantly for us, when spectators can also show up in numbers to watch, but my opinion would be to definitely finish the remaining fixtures for this season as scheduled and then devise "something else" for the 2020/2021 season where everyone knows what's happening beforehand.

If the full league structure could be completed in the time logically available, then that would be what everyone would prefer.

If there is less time, then maybe a version where teams only play each other once might work?

Split leagues (top half/bottom half) based on positions at mid-season?

All manner of weird league/cup competitions could work as a stopgap.

Can't imagine everyone would be happy though...