I understand the complain about Moon Druid, so yes, that would be nice. Though I also could see an option where you get stronger self-alterations (natural attacks, tentacles, wings, more AC), or stronger forms (humanoids, giants, dragons, with a HD max, or just a few fixed forms). On the samen note (thematic focus): I also miss that in the caster department. It's really a shame 5e didn't continue on the path that late 3.5 took, with the beguiler, warmage, dread necromacer - powerful, versatile spellcasters but with a very specific theme, and different strengths and weaknesses. The generalistic approach leads to too much the same spells be prefered (fireball, fly, invisibility, shield, absorb elements, banishment, misty step, animate object, wall of force, etc. etc.) regardless of subclass / school focus.