If you put only soil for the hills on blacktop you will probably end up with cooked plants considering how hot it gets in your zone... unless you wait till fall to do it.
Yeah, you'll want to be careful about those vining plants once they spread enough to get on that blacktop. You're going to need something to protect them from sitting directly on the pavement... maybe some old tires. You could make rings around the piles of dirt. That way the vines would sit on top of the tires and not actually touch the blacktop.
Hey! This is an old tennis court right? is the net still there? If so - bingo! Ready made trellis!
^ Even if the plants stay over soil they may be a lot hotter than if placed elsewhere. Asphalt in summer sun can get hot enough to cook an egg. If the space must be used I would cover the entire area with soil... but really, if it's not going to be a court anymore the blacktop might as well be removed.
One reason they are planted in hills is to help prevent crown rot. If you plant flat and the crown happens to be in a depression that holds more water, you are begging for crown rot. These plants don't grow upwards like most other plants so it's important to insure that there is good drainage around the crown. Planting in hills achieves this.