I've done a lot of mixed-gender training rides over the years and definitely have developed some likes/dislikes. I prefer groups that offer different subgroups to cater to faster/slower speeds and experience levels. I'd suggest having a no-drop policy, but I'd add that all of the group rides I've done have had marked routes, which is helpful for those (like me) who don't necessarily need a no-drop policy but do want to know how to get back to my car. If I were putting a ride together, I'd try to find a route with low traffic, decent road surfaces, good sight lines and no loose dogs.

Most of my frustration during training rides had to do with lax etiquette and safety issues. I think it would be helpful to offer some instruction on how to safely and politely ride in a group/paceline. I also think it's important to establish and enforce some safety rules and expectations, not just so that no one in the group gets hurt, but also to maintan a positive relationship with vehicular traffic. Some of our local training rides have really gotten crosswise with the community because they don't respect the rules of the road. I would repeatedly make it clear that stop signs will be respected and that the group will only ride two-abreast when conditions allow.