IMHO if there is to be a hope of R some of the bricks need to be removed from the wall you have built around you because of his affair. It can be one tiny one at a time and there will be times when all the bricks fly back into place and it all has to start again. If you are interested in vulnerability search for Brene Brown on YouTube. I have found her to be very good!
So yes, DDay shifted all the power to you. Offering R means you're ready to shift it back towards balance. It's not saying what WS did was okay. It's saying you still see a glimmer of hope. It's saying WS just may be a good person who made bad choices.
You still get to set your boundaries of what you will and will not tolerate in your M. One of those is probably a recurrence of infidelity. I know that's one of mine- I will try to R, and I will try to live with the knowledge of what he's done. But there is a chance that I can't. And, if he does it again, I will have no guilt or regret in choosing to leave at that point.
As I read your post, you told your H what you need to experience from him before you commit to R. IMO, that's the best way to get what you want from him. After all, he can't read your mind.
And you're saying, show me you're worth fighting for, then I'll decide what I want. You make a promise of a sort - to decide - but that doesn't mean you'll decide the way he wants you to.
I don't see any weakness there at all. JMO, of course.