Reins of the Raven Lord: 1.8%... No big deal, I can go in and solo it.
Deathcharger's Reins: .8%... A little low, no big deal, I can solo it on my level 60.
Reins of the Bronze Drake: 100% with timed run... There's a reason it's called the ghetto drake.
Reins of the Blue Proto Drake: 1.6% Still soloable.
Reins of the Blue Drake: A whopping 6%... ONLY in a random LFG dungeon (which brings the rate down to .375% or so 6%/16 LK dungeons), OR an astonishinly low drop from Maly25 (as if anyone is willing to run that instance, not even guildies...), OR an astonishingly low drop from the goody bag which is only available to tanks and (somewhat rarely) healers. The same goody bags which has spawned an epidemic of fail tanks because a Plate DPS decides they want one, so they will queue tank without diddly for gear, no enchants, no gems and NO idea HOW to spec properly (but that is a rant for a different post...).
Reins of the Azure Drake: 1.7% drop on a raid that (again) is SO annoying, you can't PAY people to run it.
Reins of the Twilight and Black Drakes: 100% No problems getting people to pug that one for a chance at them.
Does Blizzard really NOT see a problem with these figures? And now if you want to run end game content, or, really, any raid, you can't lock down at 80 to farm this.
Now on to the suggested fix: Either make an 85 version of it (not necessary as well as difficult and time consuming) OR... (ready for this?) make the Cache of the Ley-Guardian 100% drop for anyone who WALKS into the instance. I know, isn't that an amazing idea? Simple as that. And the best part is, People still won't be able to solo it, due to the drake riding, so they'll HAVE to bring a few buddies...
Oh, and remember those Reigns of the Azure Drake mentioned above? Why not throw them in too, and make both 3% drop (splitting the drop rate from above), or even 1.8% like the Raven Lord?