Right now druids are very limited...instead of being the "nature-oriented" casters that they should be they are restricted to mere potion making. I know that more druid magic is already planned, but I think it would be beneficial if specific new druid spells were proposed and brought up as there seems only to be a vague idea about what in the future druid magic will be like...To start off I propose the following druid abilities/spells for the future:
Charm - Allows a druid to control a animal's movements even allowing a druid to make the animal attack.
Constricting vines - Causes vines to spring up and hold the target in place (like xxx xxx...)
Rapid growth - Causes all plants to grow at a faster rate? (so trees, crops could all benefit)
That is all I can think of at the moment.

Also I think an appropriate magic system for druids could be based on runes...as runes are very ancient/basic and tied to nature...any thoughts on that are welcome.