You could just oh say give him a little note or sheet of paper to read where you list out some of the other stuff you would like to try (use your imagination as opposed to some pre-made list) and give him a nice blow job while he reads it.

Say something like:

I love you. I know that being in a relationship needs open and honest two way communication and that being in charge can be vexing sometimes and that knowing me and my desires as well as your own can be helpful. I love you even more (is that's possible) since we started getting kinky and I hope your having as much fun as I am doing what we do. What we are doing already is great so don't get me wrong but if you want to explore further and maybe see just how far this rabbit hole goes these are a list of some of the things I am very interested in trying with you if you also desire to experience them.

Most of my own conversations about limits and what I would like to experience with a dom have all occurred while "in scene" as some people like to say. (Think kinky interrogation of a slave while she is giving head or while in a humiliating position etc).

Its also vital that you have some kind of two way open and honest communication going on without fear of reprisals.