Is it any wonder then why he had that crush on Donna? (He also had a crush on some Rena girl back in his Robin days. I've begged a friend of mine to post it here. But if you had it... I'd love to see it. ;-D)
As a fic writer myself, I've explored the sibling angle before and the romantic one and it a workable premise with Steph.
Steph does have the Daddy Issues, but I just like her with Tim. It's too cute for words. Rose/Jason would be interesting, but they are also a lot alike. Plus it could be potentially enabling. But Mia? Yeah. Plus she's got Daddy Issues, lived on the street, etc. Yeah, Jason/Mia. Count me in on that train.