Vigor will also find use for raid events. At high rank, in fights with other players joining, it's not uncommon to have raids fights finish within a couple turns before any major damage is done to your party, so these become more of a damage race for MVP spots, so vigor weapons can help getting that. Of course this is if you even care about MVP in the first place.

On a side note, I recall seeing a screenshot or maybe it was a video of DMM having more party set slots. Hopefully we get those soon as they can help with making alternate parties sets. Especially for me, as I am lazy to the point I don't even want to swap my teams out to do R or SR only event missions.