A real quick summary:
- Wild shape is, IME, what makes many people want to play a druid.
- In practice, it creates a huge pool of extra hit points that makes druids weirdly durable.
- Wild shape damage also lags at high levels.
- Because the druid is a full caster, we don't have a big power budget for subclasses.
- All of that together means that circle of the moon packs a ton of core functionality that anyone who likes wild shape wants. It makes designing alternatives difficult.
I'm really looking forward to the 2024 refresh of the druid. I know the ranger and monk get a lot of attention, but my experience working on subclasses showed me that the druid is the most difficult class to work with.