too much line blurring!
Well, the druid distinguishes themselves from the Cleric proper in my campaign by not being part of a church heriarchy. The druid doesn't build temples, minister to the poor, or do anything unnessecarily kind like that. She advances the causes of nature, above all. The druid that's playing in my campaign even worships a goddess, but only for her role in nature.
The druids, IMC, are an international network of spies and secretive folk that live thoughout the world, specializing in learning it's varied flora and fauna. They have connections. They know things only hinted at to those who live in cities. They're useful contacts and they're frightening enemies.
Of course, my campaign also has the Shaman and Shugenga. Shaman are much more tribal-elder type. They'd be a cleric if they were from a culture that had full plate.

As it is, they're a bit more primitive in their animistic outlook, and it shows. They're kinda a hybrid between savage druid and cultured priest -- a middle ground.
Shugenjas, IMC, don't have the trappings of civilization around them -- they are the class that has been touched by the gods, in a similar way to how sorcerers are touched by dragons. They are the living saints, the true scions of divinity, Aasimar who are watered down enough to be nearly human. They arise from the ranks of the druid, the cleric, and the shaman, and may be indistinguishable at first.
I'm not sure what the problem with Druids is, personally. They've always been different and unique enough to catch my iterest.
...and druids do *not* need more healing. As far as magic goes, their clerics with firepower, too. They're not as concerned with helping those who cannot naturally overcome their injuries, though they will provide a bit of aid. They may refuse to heal someone who is only a bit injured. The druids know how to manipulate the forces of nature, and that often means destruction of those foolish enough to violate it.
Druids can be plenty worldly. How else will they get those fools in the cities to listen to their pleas, unless they "speak the language of gold." And though the mundane trappings of civilization hold little appeal for them, the major ones do. Enough money, and you can buy land from those who own it, and set it aside as a sanctuary. And that may be much, much more effective than simply leveling it later with an Earthquake, and having many, many angry humans breathing down your neck.
So, what's wrong with 'em?