Thanks Ladies! When searching last night, I looked at Electric Quilt, but if it does what I'm looking for, you can't tell it from their preview.
@Deafoldbat, your complaint about it is something that would drive me mad, so it sounds like a good one for me to stay away from!
Quilt-Pro never came up on my search, but it looks like it has the capability I'm after. They also have a couple quilt coloring books on their site, which are exactly the kind of thing I'm hoping to create, customized to my own designs. Those are only $10, so I'll start with those and see what kind of options they have while I'm discussing the bigger purchase with hubs.
Thank you!