Huh, I saw a spark between Ron and Hermione from the beginning. Certainly in book 4, when she told him that he should have asked her first if he wanted her to go to the ball with him.
Your ending would have been... interesting. My ending would have had Harry lose all his magical powers and live quietly on the edge between the magical and Muggle worlds.
Heh, my favorite Ron/Hermione moment in Book 7, was when Ron came back, and Hermione pitched a fit at him, wondering if there was anything else he could think to say, other than "I'm sorry".
I think she was wanting to hear the "three little words". ;)
That the biggest prediction I got wrong (ok, that and Hermione dying, but I KNEW I was reaching there...) -- in the literary tradition she followed, he should have had to give up something of that degree to win the final battle. I suppose all of the sacrifices he made, and were made for him, make up for it, but even so...