[5e] What is the general progression path for a Druid? I supposed due to options this is a pretty broad question, but let me use an example:
Level 2 Druid, Circle of the Moon. Average health, about 14. Preferred Shapeshift: Direwolf, Average health of 37.
Level 5 Druid, Average Health, about 35-40. Best shapeshift: Still Direwolf at 37HP.
The falloff seems pretty dramatic here, of course starting at level 6 you get access to CR2 stuff, which opens up say...
But where do you go next? The options at level 6 are pretty balanced for a level 6 as far as I can tell, but you don't get any new options until level 9 when you gain access to CR3 stuff, which, actually seems to be worse than just not shifting at all. This of course changes in a mere one level as Elemental shapes are reasonably strong for the level required. Again though, those forms only (seem to) maintain relevance for a while before losing steam.
So, am I just completely missing something obvious, or are there really just these weird ramps in power. If there are weird power ramps, is it reasonable to just come up with homebrew in the manner of just cleanly scaling a creature's statistics to fair numbers per-level?