It sounds like you're on the right track. Husbandry sounds pretty good and those temps are fine. You'll just have to watch your humidity because of the light. However, if you stay on top of it, it shouldn't be a problem.
At the expo, you're going to find A LOT of babies. Since you're on the hunt for females, keep in mind that the price of a female goes up as it gets bigger. Starting off with a baby should be find in that setup. While the baby is still young, I'd buy A LOT of fake plants/vines to clutter the cage. You want it to be so cluttered that you can barely see the substrate. The little snake needs to feel secure or it won't eat for you. That'll be your biggest problem with a small baby in that large enclosure. In fact, I'd offer a few more hides. Sometimes, having 3-4 hides can also help.