Reconciling a desire for sex and obedience within a switch relationship

I'd like to see what people thoughts are on a small conundrum we have within our switch relationship.

We are a kinky switch couple. Myself (M 39) and my partner (F 31). She very much enjoys being submissive for the most part and that aspect is great. She does very much enjoy the opportunity to be dominant and I'd say 30% of our sex life she is.

For me, chastity is the key to my obedience. I can't just click into a submissive role, it takes a process and chastity is that process. When I'm locked she knows that she has my full attention, that my desire for her becomes intense and because she is hypersexual, that very much pleases her. She really enjoys getting the level of sexual attention it produces in me. One thing I think it's unique is that she likes to dictate but sometimes the instruction is to beat her, indulge her fetishes, and other aspects of our D/s relationship.

The "problem" (and I put that in inverted commas because it's not a problem, but more an obstacle to us/me making this as effective and satisfying as possible for her) is that I will do anything for intercourse after a day or two. She will do anything for penetration and so when we both get super horny, she invariably unlocks me, we fuck and I go back to a normal level of desire.

I think I'm too persuasive, we both know I can convince her. I want it, she wants it but it ends the fun.

We love numbing cream, but I can sometimes still cum. It's desperate, long lasting and intense but I can still get there.

Wearing a strap on is fine, I find it a bit humiliating and she doesn't feel it's a satisfying end to play.

She loves that I'm aggressive and charged up and she "let's me loose on her". It satisfies her love of dictating.

So how could I make better this scenario. I'd like to have periods of weeks were we really indulge this dynamic, where she feels truly empowered and satisfied for more than a day at a time, but where she can still be fucked in the way that she wants.
One thought I'd that we need to have a trade, something I lose, a punishment, that's realistic and a genuine deterrent for me should I cum. That's challenging because what could that be that would trump an organ when charged, free and driven to fuck aggressively...

See the conundrum?