My 5 year old is still in preschool, and they have mandatory rest time at school, which we do at home on the weekends as well. I do notice a big difference in her behavior if she doesn't have that time to herself. She sleeps about half the time. We always do the same routine: Potty, book, snuggle, bed. She takes a nap at the same time as her infant sister inthe afternoon. I put on soft soothing music (they seem to like Enya a lot), shut the curtains and tell her that we are ALL going to have a rest. I tell her she can come down from her bed once to potty, but has to stay in bed and very quiet until I come and get her. She gets to take one book up to her bed with her. Hope that helps you.
Regarding the blankie-I don't know when it is the "right" time to start the process of separation, but there is a great book by Kevin Henkes (if you haven't read his stuff, it is just hilarious!!) about saying goodbye to the blankie. It is written for kids, so you can read it with your son. In the end, his mom makes him little hankies out of his blankie, so then he can take little pieces in his pocket. My daughter never had a favorite "Lovie" so i guess I lucked out. Too bad we can't take away the thumb!