I can't speak to what current/future design choices hold with regards to superraids, but I much prefer them during fusion tourneys (like we have been getting recently) rather than during drop fevers for the purpose of saving time, if I had to choose one.
Why can't they be an all the time thing?
They should also be for everything, the amount of time you have to spend in this game just keeps increasing.
Besides the thing that seems to motivate them more than anything is $$$$ and Super Raids would be a cash cow IMO, people would be burning thru energy like it was water.