For my original project band I only need one bass, tuned in E, with a Hipshot to drop down to D.
My last cover band was another story. To minimize the "dead space" between guitar & tuning changes I needed 3 basses minimum - one tuned to E with a Hipshot to drop to D, a second tuned to E flat (also with a hipshot tuner), and a third to cover the drop C & B tunings. Probably would have been much easier if I played a fiver, but they just never felt right to me.
My last cover band was another story. To minimize the "dead space" between guitar & tuning changes I needed 3 basses minimum - one tuned to E with a Hipshot to drop to D, a second tuned to E flat (also with a hipshot tuner), and a third to cover the drop C & B tunings. Probably would have been much easier if I played a fiver, but they just never felt right to me.