So I need to re-gain the interest of a girl and I am looking for advice or opinions.

This girl is a friend of my sister and I fooled around lightly with her a few years ago but have not seen her much since. A couple months ago she visited when my sister was home from university, she recently broke up with her boyfriend and I am pretty sure she was giving me IOIs. Also I don't see her when my sister is at university. So a few weeks go by, i sent a couple humorous/flirty messages online, and then I get the opportunity to invite her over to help me with something. When she comes over I make a move and make out with her. I give her the opportunity to stop but she wants to continue. Eventually we have to stop at which point she has the opportunity to leave but chooses to stay and we make out again within the next hour. She then tells me to text her before she leaves. i wait 3 days and text her, at that point she texts me everyday for a few days. The weekend comes and I try to set up a date. She didn't give me a straight answer but indicated she wasn't feeling well and kind of left me hanging. Then her texting slowed down. It took a couple weeks but I got her on a date at which we did some kissing, held hands, stoked her leg in public. At the end she indicated she had a good time and gave the impression we'd go out again. Then a few days later she tells me its weird and she doesn't feel that way. I get my sister to message her and this girl says she views me as a brother figure. Which my sis says is very strange but this girl has led guys on before.

The plan:
Oddly enough I have a stange attraction to her and feel like giving it another shot. Here is my plan, I'll confront her on the brother thing, play along with it, indicate that if that is the case then she owes me some serious brother sister time since we've had none. Try to convince her to take me out shopping to look for clothes for work or to meet girls. Then if she agrees neg her on pick up, while looking for clothes try to number close other girls in front of her and try to get her to pay for some of the clothing items for me. Give her joking nudges. Then on the way to the car do a little kino up her back, and pull her in for a make out kiss before she gets into the car. If it works tell her that I am definately not like a brother, I am in a whole new league she has never been in before and there is a lot she doesn't know. Then wait 2 days and send her a pick up text. If it doesn't work then I'll have to wait and hit on her if I see her around Christmas.

Any thoughts? Opinions? Better ideas?