For what it's worth, you could argue that a Druid is like a Divine caster, with their Higher Power being Nature. You could merge it with Arcane casting, and flavor spells as, say, vines and thorns.
I absolutely agree, in fact I always thought that Druids in 5e would be a lot more interesting if they were combined with clerics to form an "Invoker" of sorts. You could make the less than stellar Cleric Channel Divinities be the Druid's Wild Shapes from Subclasses.
And while flavoring spells could fit with BDP the main problem I see is that it doesn't really offer the ability for a shape changer style of character. Same goes for a character that wants to let their pet do the fighting, the Animal Companion is good but I am currently allowing people to take it multiple times which will give them a more powerful pet.
Finally I noticed that unarmed attacks aren't stated to have a speed. It is most likely fast but I still wanted to mention it.
Yeah, good points!
I'll think about shapeshifting - that could be an interesting thing outside of Druids, with a variety of different interpretations (is it a mutation? Polymorphing? The Holy Spirit enhancing you?).
I'd put unarmed attacks last generally, yes, since their damage die is essentially already Impaired.