Our flock is let out in the morning, anywhere between 7-9 AM and they start heading back to the coop when the sun is going down. If I want them in a bit earlier (ie, if we are going to dinner or something) I "bribe" them in with crushed corn, or scratch in the coop- that brings them in EVERYTIME! :0)
Yeah, our girls go in on their own too, but I do bribe them with treats if I want to close them in early- when my laziness prevails!
We feel your pain, our girls werent out much over the winter either, we ended up raking them a path from the coop to a boat trailer, and they would walk over the packed down snow to get to the trailer, although some evenings they just simply didnt want to walk back over the snow so we would have to carry them. Spoiled chickens!
I have the same problem with predators. Usually I just wait until later in the afternoon, let them out when I know I will be around, and then let them put themselves to bed in the evening.
Throwing out some scratch or the kitchen scraps bucket (aka the "chicken bucket") work really well too. You kind of have to train them to come when you call then they will get back into their run more quickly. I call mine "chick, chick, chick" and they come running!