Well, for this I usually stick to the order the AUs were actually created in! (Not necessarily the order they posted in, because we opened up the poll for deciding which story posts next). Not that all apply this way, because some were actually designed around this concept.
First is of course
Brothers Apart, and that’s in front of all other AUs. The original, the first, the basis for all that follows.
It’s followed by the main ones that we’ve played around with–
Maybe if she coaxes them to go to a different motel they’ll keep away from her little experiments? She might lose Sam as a curse victim, but there are other ways in Brothers United.
No more Walt to bother her Sam in Brothers Unexpected…
Following that is
Brothers Asunder, when she gets fed up with Sam and Dean. Bowman better watch himself there. She’s seen him interfering a few times.
Sherlock should watch where he sticks his nose, because one of these days she might not just leave him to be the Consulting Detective like he enjoys. Stan got himself in some trouble too, leading to
currently takes place last, though there may be another AU placed around the same basic period with Celeste. Here she’s thrown out the rules and tossed Sam and Dean into the (currently) worst case scenario.