My last gig was pretty much sitting (jazz) unless I was having to balance on 2inch square of stage.
For a more active band I think I'd want a chair that I could get up from when I felt good enough for it. If the set is planned in a fairly conventional way - first 3 tunes being high tempo, then next 2-3 a bit slower etc etc then I'd probably stand for the first ones, then sit down for a bit - maybe even up to the finale.
But that depends on the extent of injuries of course.