I have started to play diablo 2 ressurected recently and i am still impressed how flexible playstyle does druid have. I was thinking how to put this character into heroes of the storm and these are my ideas:
the role would be most likely a Battle-mage hybrid who can shapeshift into Werebear form (D) which increase your HP by 25%. With this ability you can partly substitute frontlane when needed. There should be a short cooldown after swaping to Human/Werebear form.
for (Q) ability I suggest a basic melee ability called Maul. To cast Maul, you must be in Werebear form and it will damage all enemies in front of your melee range. You can store up 3 charges of Maul and subsequent Mauls will deal increased damage. There would be a 1 sec global cooldown to prevent using all 3 charges at once. Cooldown of Maul can recharge while not in Werebear form.
For his (W) ability, you could summon a raven that would grant vision in a specific map area for limited time. Usable while in Werebear
His (E) ability could be some iconic elemental skillshot like tornado which would Slow/snare and damage all enemies it hits. You cannot use this ability in Werebear
Druid’s (R1) would be Volcano spell - which creates a crater (impassable terrain) that also bursts all nearby enemies after a short period of time (Good in combination with Tornado root)
(R2) would be Shockwave - AOE stun, usable only in Werebear form. (Good to hit all 3 Maul charges)
Regarding talents, there would be Two ideal types of playstyle, but in reality you shall always play the hybrid.
1st playstyle - Werebear oriented - Armor bonuses while shapeshifting/ increasing mobility or movement speed and basically all frontlane stuff.
2nd playstyle - elemental oriented - boosted damage or charges of tornado / cyclone armor for survival of burst damage/ Adding Fissure as an (+) ability on lv 20
When I am thinking about it, it kinda reflects the shapeshifting feature of Graymane, but in the essence i think combining control-mage with Tank features is quite original. I also think that Druid players from WoW will also identify themselves with this playstyle.