As a new member one thing I really enjoyed was the new members mingle, in particular the use of colored dots to identify the different types of riders (fast, touring speed, slow and easy). It was nice to quickly find people with common ground.
On the Wednesday night rides that I have joined the way to find your group is to start riding and see which if any cluster you end up in. Sometimes you find a group, sometimes you ride solo or get dropped. Even if there are others of your speed if they start ahead of or behind you then you might not get together since you're all riding at about the same speed. Apparently if you ride often enough eventually you figure out who rides at your pace.
So here's an idea. Forgive me if it has already been tried, like I said I'm new. How about all riders put one of those colored dots on the back of their helmets. Then in the parking lot the ride leader ask people to start based on color, first red then yellow etc. The dots could be given out as needed by the ride leaders; eventually most people would already have them.
By doing this riders could find their own kind before the ride and would have a better chance of riding together. During the ride if you see your color up ahead you might sprint to join that group, or if you see a faster color you may choose not to try. Of course people could ride with whoever they choose, the colors would be an aid not a regulation.
Comments are encouraged!
It's funny you mentioned the Wednesday night ride because I've stopped going to them because I end up riding by myself the entire way (I average 14mph on those rides). Not sure if it's that I just get behind and can't catch up or what, but I've decided it's just not fun. Someone suggested doing the Slow & Easy ride which I might try next year, if there aren't any better options closer to home. I agree than it's frustrating. Your idea of putting dots on helmets or figuring out some way to find like riders in a large group like that is a good one.