West Thumb Geyser Basin is pretty small, but is worth visiting since it sits on Yellowstone Lake, which is amazing. The thermal features located here aren’t all that great, but the ones in the lake itself are pretty interesting/different than the rest of the basins you’ll visit.
Biscuit Basin is a lot of the same, although they do have a couple of fairly active geysers that are always erupting, if you’re patient enough to sit around for 10-15 minutes. I would have probably skipped this one altogether if the Mystic Falls trailhead didn’t sit behind it. Still, nothing you can’t see at Norris or Midway.