I wonder if this is going to be a reasonable approach longer term - I mean, druids are very versatile which is why I want to play with them, and I can always change spec for fights where all Guardian won't work, but I wonder if at some point I'm going to hit a wall where I'll need to go back to the holy trinity style of play or, at least, having an actual healer.
All druids sound so fun, I might start up another team again. I used to love running around as all trees, thought it looked cool. I also liked to do this thing when I 10 boxed where 5 toons switched to cat and 5 switched to trees and the cats looked like pets of the trees. My druid team was years ago though, think up to level 90.

The closer you get to 100 the less likely you'll stay all tank, stuff starts taking too long to kill. But I don't think you will ever have to change, you can 5 tank or 5 dps or even 5 heal dungeons at end game.

I'm a fan of hunters this expansion.