I was recently reading about Skyrim, when this chart caught my attention. These are the 18 confirmed skills in Skyrim. (You do not choose from these three, you have access to all of these skills, their only divided up into three separate categories for simpler navigation.)

WARRIOR
-Archery
-Block
-Heavy Armor
-One-Handed
-Two-Handed
-Smithing


MAGE
-Alteration
-Conjuration
-Destruction
-Illusion
-Restoration
-Enchanting


THIEF
-Alchemy
-Light Armor
-Lockpicking
-Pickpocketing
-Sneak
-Speechcraft

When I went over this, I began thinking, if a person who focus's mostly on the thief skills, what would this mean for combat against dragons? Thieves would specialize in light weaponry and possibly archery for combat, but against dragons, they most likely lose their main element of attack, which is surprise. Perhaps I'm just underestimating the class, but I find that it would be somewhat unbalanced as far as fighting beings like that (Taking out the use of the dragon shouts.). Warriors would have the advantage of high damage output with weapons more appropriate for dealing more damage, and more likely using heavy armor, they'd be able to resist damage more effectively. Mages would have access to a large array of spells, some capable using at long range safely away from a dragon. To me the ones that opt for much stealthier characters are put at a disadvantage against dragons, given appropriate surroundings.