Before release, dragons in Skyrim were touted as being different from the typical fantasy that we're used to, that they don't just breathe fire or ice (sorry, no quotes/links right now; may edit this post with some). In my Collector's Edition art book (which I don't have at this moment, so again, may edit to quote later), there's a concept piece of Alduin shouting at some soldiers who are sent flying, presumably by using Unrelenting Force. The artist, who is quoted on the page, mentions that he was happy to design a dragon who wasn't simply breathing fire or frost. I'm pretty sure that the "making of" DVD that came with the Collector's Edition contains other developer comments regarding the uniqueness of dragons, but I'll have to watch it again because it's been ages.
The point is that we were promised a unique dragon-slaying experience and that promise was not kept. Instead, we have typical dragons who do nothing but breath fire or frost (the very shouts are called "Fire/Frost Breath") and use melee attacks. The only thing unique about dragons is that the player cannot use the version of the shouts they use. Even games like Monster Hunter and Dungeons & Dragons have more variety (and with dragons who have more combat tactics than just breath weapons and simple melee). The Greybeards themselves tell us that a fight between two dragons is actually a deadly verbal debate (a loading screen and something in the art book say the same thing). What's the debate about, two dragons yelling "Fire Inferno Sun" and "Frost Cold Freeze" at each other? For goodness' sake, Draugr use more shouts than dragons!
Furthermore, dragons actually shouting would change a lot about combat and maybe even force the Dragonborn to combat dragons with shouts. Here's what I'd like to see dragons using:
-Disarm
-Elemental Fury (for simply faster attack speed by dragons)
-Unrelenting Force
-Storm Call (which can be countered by Clear Skies)
-Clear Skies to counter our Storm Call
-Animal Allegiance if there are creatures nearby (countered by Dismay)
-Dismay to counter our followers and to counter Animal Allegiance
-Become Ethereal to recover
-Marked for Death (to be used on both us and our allies)
-Slow Time (countered by Whirlwind Sprint)
-Whirlwind Sprint (used to fly across the sky in a path quickly to dodge magic and arrows)
(One of the shouts I would not have them use is Ice Form for sake of balance, but seeing as how the Greybeards use it, maybe. Up to you, Bethesda)
You decide which kinds of dragons should be using which shouts at different levels. All I want to see is change; I want to see what we were promised.