Nice set of advices, but I had something more extensive in mind. Also something, which includes Land Druides, even if they seem to be less popular or maybe even not suitable for an "optimized" character.
Here's some more random advice:
Exploit Entangle and Goodberry from level 1 onwards, Spike Growth from level 3, and Conjure Animals (giant cobras) from level 5. Druids are powerhouses. Later on you can Planar Bind pixies and dryads for spellcasting backup.
Thorn Whip is usable with Mobile feat.
Mage Armor from a friendly wizard will vastly improve your AC. At level 2, you can be a Giant Hyena with AC 15 and 50+ HP. At level 10, you can be a flying, Mobile Air Elemental with AC 18.
Since you're Mobile anyway, you might as well become an Earth Elemental and do hit-and-run from below, surfacing only long enough to make an attack and then burrowing back down again. Once Archdruid comes online you can use Contagion instead of a strike with your fists, since Contagion is still a melee (spell) attack.
For rampage fun, gather a horde of Mice and use Animal Shapes to transform them all into birds. Fly to your target location and then turn them all into Giant Scorpions or Giant Constrictor Snakes.
Sentinel is a pretty good feat for Moon Druids with melee buddies; it can increase your damage output by 50% to 100% if they target your buddies, and if they target you they're just burning fake HP anyway. Remember, you can always Dodge, even in animal form.
Giant Crocodile form at level 15 gives you two ways of giving advantage to your allies: inflicting prone and restrained. Giant Anaconda form at level 6 gives only Restrained but is still great in a ranged-heavy party.