Does Edward still have no kids? And does he outlive Mary? Which would make who gets the crown a toss-up between Janey and the is-she-isn't-she Liz Tudor. What about a marriage between Liz and Erik, while Jane is engaged to the duke of Finland, but before the marriage goes through, her brother and elder half-sister die. While Liz is already in Stockholm. I'm not sure how the English will react to their new queen being married to a foreigner (especially if she's married and living in Sweden at the time she succeeds, and a spinster Liz is still in England)