I get a large number of women telling me that they worry that they are not doing enough, or the right things, to keep their partner satisfied. First of all, and I have said this until I am blue in the face... It is NOT about his pleasure, it is about yours!
Many women fear that they are not doing enough, or that he will get bored with the things they are doing. I can understand these feelings. I have been there myself. However, I came to the realization that I was creating my own fear. I had a fear of failure, of not doing it right, or not doing enough to keep him happy. It is not about him!
To put it simply, you should not be doing things FOR him, but TO him. You should be doing things FOR YOU! Don't think in terms of whether or not you are pleasing him, but rather, is he pleasing you? You are (or should be) the focus of all he does. It is your job to make him focus on those things. If he is not happy doing that, then he may not be cut out to be a submissive.
If that is the case, it is up to you to mold him into the man you want him to be. If he is bored, shame on you. You are not giving him enough to do to keep him aroused. You are, probably, not using his fantasies to your advantage. You should learn to do that. If you are doing it, then do it more often. You can always have him do a webtease. It not only keeps him busy but, usually, allows him an orgasm. Maybe you should make up (or modify) your own webtease that does NOT end with his satisfaction, but rather your satisfaction.
Your partner should be coming to you and asking what he can do for you. If he isn't, then he is not aroused enough. If he complains about not getting enough (sexually) then find more ways to arouse him without having to satisfy him.
Nine times out of ten, if things are not going right, it is because you are creating your own problem. If you keep in mind that it is not what you do for him, but rather what you do to him for yourself, you will get along much better.