It just sounds like to him sex is not his number one priority. To be honest, you should be pleased in someways lots of girls want guys that are so considerate.
From what you have said, he sounds very intrested in you and he likes the sex you do have so I don't really see why there should be a problem. Maybe he just doesnt want a relationship which revolves around a sex life. Some people don't actually want sex once a day. I think the average is once every two or three days. But this doesnt mean he doesnt want sex with you at all!
Maybe you should talk to him about this, as I'm sure hed be able to reassure you completely. I'm sure if he knew you wanted him to initiate things more he probably would as well.