Hmmm....let me think
You seem to have most of the bases covered. I can think of two options, one easy in the short run, but tricky in the long run. And vice-versa.
Option 1: Share hobbies. Do something with her that she likes doing. If she likes going to fancy foreign films or something, go along with her. Even if it bores you to tears, don't let it show. Spoof her by saying that it's interesting and draw the conclusion that you are way more fond of her now that you can see she has substance. Also get her to share your hobbies. Ideally, that would be riding, but in the meantime, take her racing one day*, or to a soccer match.
Option 2: Tell her you think you are falling in love with her. Might work, but a world of pain will ensue. Depends how desperately you want the ride, and whether you think she'll swallow it (insert Merlin joke here).
* You will need to stick your bets on in the morning, as some birds aren't that keen on gamblers. When you do your nuts in the bumper, try not to show that you have lost 200 euros in one race.