I tend to write one-sentence "biographies" (because my interest is genealogy, not biography), and in-line citations just don't work for my way of thinking, so I use your method 3, slightly differently formatted:
*[URL Source Title]
:transcription
:transcription
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An example of a source title is "FamilySearch Film #004836096 Image 225 of 776 (Baja, Bács-Bodrog, Hungary, civil registrations, births): Miskolczi László, 1900 Aug 9".
The colon is the solution I've found for circumventing WikiTree's insane appetite for line breaks. It was either that or hard HTML breaks ( < b r / > , minus the extra spaces); I chose the colon because it's possible to type without changing keyboard layouts*, and besides, it allows some extra indenting to match the format of things like funeral notices (which often have the name of the deceased indented or centered).
*99% of my transcriptions are in Hungarian, for which I switch to a Hungarian keyboard layout, but I haven't a clue where the less-than sign is in that. Of course, it loses square brackets, too, so I always have to do some switching.