I'm beginning a new character with a rather more involved role play and I have been trying to find out when the most frequent appearance of dragons occurs based on which stage of the MQ has been completed. So far my perusal of the UESP hasn't really turned up a definitive answer, so I am appealing to my fellow Skyrim goers' experience as to when during the MQ do the most dragons appear?
Extraneous info
Some of the elements of this particular role play will be:
Use only found spells (except for those that don't appear as findable spells in game). I've done this in the past and it is amazing how excited one gets when finding that one spell like muffle you've been trying to locate for what seems like an eternity.
Learn enchantments from found items only.
Amass a complete in game Library and rescue all books whenever possible (selling duplicates to Urtag for safe keeping).
A mostly non-FT play through in jog mode. (Exceptions would be, for example, subsequent trips up and down High Hrothgar after the first one).
Use only armor that I make myself or find in a dresser, that is, I won't be wearing gear from the dead (recent or otherwise).
Obtain Winstad Manor to be my place of solace in the north away from the cares of the civil war and other happenings in the world.
There's more "conditions", but I think you get the idea.