Listen to your red flags. Although both #2 and 3 are probably wonderful children and families but, I would go with #1 as your comments were all positive. Parents that are on the same page~ little one who would fit into your already daycare group.
If your worried about taking on another young one...red flag with the other Mom, go #1. For your busy days come September then it won't be as much work as a younger one.
Good luck!