- Druids are versatile and can be good in melee. Flame blade is a good weapon. The broken concentration is the problem, not the weapon.
- "Probably" is not an argument but anyway, you can wildshape during combats.
- The bear and the bird are usefull in combats and the bonus action add a lot of versatility. The wolf is also interresting in a group (critical hit).
Your image mirror can avoid 3 attacks. Such is the bear depending the ennemy, without spellslots, 2 times/long rest. Its damages are good for the first half of the EA. It become a meatbag after that, which is fine to me because you have all your spellslots to deal damages.
It will probably be upgraded at level 5. I think a multi attack will become necessary.
Battlemasters are playing with greatweapons because GWM is broken because of the so easy advantages.
I just ended a solo playthrough with a moondruid.
Anyway looks like you want to argue. I don't and I'm tired.
Good night and good luck with your suggestion
