Francois I of France quite possibly may have won the election of 1519. Understandably, the longterm implications of this would have been immense.
As for the Hapsburg lands, they might well have been subdivided between the princesses, although a war of inheritance is more likely, in some form at least. And the crafty old Ferdinand V of Aragon would be a key player in all of it up until his death in 1516, you can bet on it (and Francois I probably, too, since the time would be ripe for him to swallow up the rest of the Burgundian inheritance). You'd probably also see frantic remarrying on Emperor Maximilian's part (even more so than in OT), as he'd be desperate to secure a male heir. On a side note, it'd be interesting, actually, if he ended up siring more daughters, and just making things more complicated; or, if he did get a son, you can bet that it'd only increase the confusion, since there'd be a debate on whether or not Philip's daughters or his son had a greater claim to the Austrian inheritance.
In the long run, you'd see a weaker Spain, probably a much stronger France (until the wars of religion anyway, assuming they still take place), a more disunited Italy (perhaps with more papal power centered there, though that was already far into decline at this point, even before the sack of Rome; French intervention in Italian affairs would also go on for some time) and a very different reformation/counter-reformation I'd imagine. There'd also be no war of Spanish succession and probably no Thirty Years War, depending on how the spread of Protestantism factors in.
IMO, Francois might have been a better candidate to reconcile with Luther than Charles V, had he been emperor, but that's open to interpretation.
As for the HRE, you'd either be looking at a more unified version under Francois, if he managed to centralize it more, or (more likely) a much more de-centralized and independent entity, as its leader would lack any lands in Germany (though Francois's desire to go to war to acquire the rest of Burgundy might also factor in).
How's that for a start?