They might as well change the name of the game to "Druid's Castle Clash" because he is by far the most important character in the game.
I agree with im2awesome. you really need a good healer and druid is the only really good healer. TG good for damage in raids but if you watch a lot of videos ... most have a druid.. and less have a TG. Granted the TG is a much newer legendary hero but you really need something to heal heroes for raids so they don't die.
without a druid to keep your heroes/troops alive you end up spending more and more for spells to compensate. Heck even the top 200+ players end up using a lot of spells in conjunction with the druid to try and keep their heroes from dying.