Can’t advise on Kosovo, never been there.
I like the northern route:
I think this route would be more culturally diverse than cutting straight through Kosovo into Albania — you’d pass through mixed Serbian, Slavic Muslim, Montenegrin, Albanian Catholic and finally Albanian Muslim areas instead of dominantly Albanian Muslim ones. It’s also marginally safer, not sure how volatile Kosovo is at the moment (probably no real risk for an Australian, but difficult to know).
I just can add a small piece of information. Again I quote my LonelyPlanet from 2009:
Because Serbia doesn’t consider Kosovo’s entry and exit points to be
official international borders, attempts to enter Serbia from Kosovo
may be futile unless you initially entered Kosovo from Serbia.
Additionally if you plan to hitchhike into Kosovo, I wouldn’t take a Serbian car, since
it is unwise to drive in Kosovo with a Serbian plate.
Hope that helped a little bit. For further information about Kosovo and Albania I could help maybe too 😉
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