Although one of the most common thing was "I encounter a dragon when i fast travel to a city", and i don't fast travel. does that impact the chance of dragons? If so, that'd be weird.
For the main quest:
Spoiler
I've completed the greybeards training, and now the greybeards have nothing else to do except give me random locations of words, is that the main quest? I've got an innkeeper asking me to go to a dungeon as well. (i think thats the main quest lol)
Also, 2 of my 4 dragons werent random encounters, one was scripted, and the other was when i went to kill it for the bounty.