I need advice from married men.?

My husband and I have been together for 5 years. We already have great but sometimes I want more. He's not a prude or anything I think he's just perfectly content with the that we have now. The only time we ever dabble in the things i'm interested in (like light and S&M) is when we're drunk and i love it so much! I've never asked if i can do things to him that make him uncomfortable i just want him to do things to me. I've tried to tell him that i would like for him to add more things to his repertoire and he gets offended and thinks that he's not pleasing me and that he's not a good lover. how can i introduce more things into our life without making him feel impotent?