For the longest time, I played pure vanilla, and became quite accustomed to how it played. I recently installed a good number of mods, mostly cosmetic in nature, and haven't since had a single random Dragon encounter. This is annoying; I can't unlock my shouts.

First off, with my current playthrough, I took the main quest up to where I meet Delphine, and then told her "I don't have time for this." This should have affected anything, as previous characters have encountered plenty of dragons prior to this point (even during that first hike up to High Hrothgar).

I have the following new plugins installed (via Nexus Mod Manager):

* ApachiiHair
* ClimatesOfT%amriel

* StaticMeshImprovementMod

* StaticMeshImprovementMod-DragonbornTernFix

* Radiant and Unique Potions

* SkyUI

* iHud

* Book Covers Skyrim

* ethereal_elven_overhaul

* Purewaters

None of these mods should have affected the rate of Dragon spawn, I don't think. Could one of them be the culprit, or is there perhaps something else I'm overlooking?

Do You at least have the Dragons at the Word Walls? Not agreeing to assist Delphine and going to kill the Dragon at Kynesgrove does stop Random (and revived) Dragons from Spawning in the Game.

Really. I didn't know that, particularly considering how when I used to play on the XBox 360 (maybe a few patches back), I would consistently get attacked by dragons at one particular spot on the stairway (one of those story stones or whatever they're called, the one with the nameless lady sitting there contemplating it). I haven't been attacked there in a while, come to think of it. But refusing to listen to Delphine shuts down dragon encounters? Weird. I never knew that (and had never done that in the past).

Word wall dragons are there, of course. (I think that was what I saw in a distance from Morthal just a moment ago.) And come to think of it, I think there may have been a single instance where I ran into a dragon, but it flew off without fully engaging.

I didn't realize that! You just solved the same mystery for me, too. Thanks!

That is most likely a http://www.uesp.net/wiki/Skyrim:World_Interactions called the Dragon Fly By.