I received advice from a resident in my program of interest to group by relevance.
Currently my organization looks like:
[Specialty Elective][Location][Duration]
[Elective related to specialty] ... ...
[Unrelated Electives] ... ...
I'm sure, in the end, this all does not really matter much. Personally, I found organization by relevance easier on the eyes and anticipate that there will be less mental effort needed by reader to filter out relevant information.