I'm a massive geek for using this as a metaphor, but here goes anyway:

There's a scene in the movie X-Men where Cyclops and Professor Xavier are discussing adding Wolverine to their team. Cyclops says, "I don't think he can follow orders." Xavier responds, "Give him an order worth following, and he will."

Don't try to change your vanilla guy. love him how he is. But make it clear that he is incapable of commanding dominance, until he inspires submission in you.

As for you, much of this problem is your internalization. You want to submit... do you really? If you want to submit, all you have to do is let go of control. I'm guessing this becomes troubling for you when you don't get your way.

The solution might come when he pushes you to your limits, demanding exactly what he wants without giving you the impression that he will back down from your safety word. That's a scary place, sure... but that's ultimately what you're looking for, isn't it? Submission to a strong man-- but specifically to the one you already love?

Such a thing might not be possible; you may be unfullfilled. That's the most motivating thing I can think of under the circumstances.

If anything I've suggested offends you, just disregard it as the ramblings of a tired (and creatively frustrated) chihuahua.