I love fighting Dragons. With mods like http://www.nexusmods.com/skyrim/mods/3829 and http://www.nexusmods.com/skyrim/mods/32597/, nearly every fight is both challenging and unique. You can never tell exactly what a dragon will do, if it will call for dragon allies or do one of the chaotic storm shouts or shout a mayhem-like shout that causes normally friendly NPCs to fight you and everyone else and more insane randomness.

Lots of fun and a real challenge once you start to reach the higher levels. Oh and it probably should be obvious by now but yes Arthmoor's Run For Your Lives mod linked above is indeed necesary to save the suicidly stupid NPCs from self-immolation as their dumb level 5 ass runs out to be a hero with an iron dagger.

I've always found vanilla Dragons annoying to fight, they were weak and rather pathetic, until the higher level ones started spawning. And my biggest gripe about them was that they ran off in the middle of a fight. I got you now Dragon... Wait where are you going. Watches as the Dragon chases a Elk running by... Seriously an Elk, I'm the Dragonborn. Fight Me! Not some stupid Elk.

Ya, one of my first characters had about 300 in health and pretty close to the magic resistance cap. Dragons were push-overs. Get rid of those and I don't care how much damage you can do, dragons are dangerous!

Well I play in 360 so no mods for me