I agree with GG, there's probably some middle ground that you two could reach if you're both willing to negotiate a bit.
Do I think it's wrong for you to hold her to her promise? Not really, but you have to recognize the harm it could do in the long run if she has an emotional overload and decides she can't handle poly EVER because of the speed it progressed.
Do I think it's wrong for you to complete give in and agree to wait on everything until she's "ready"? Kind of. I mean, she's working on it and that's great, but it's not really fair to you to have to deny your identity for longer than absolutely necessary.
So.. I would agree that finding some sort of middle space that you both are comfortable with (online dating profile, casual dating but no serious relationships or sex, you being able to date but agreeing to avoid romantic entanglement with people you both know or that she is in social situations with regularly, or something else that fits you two better) would be the best option.
Supporting her while she works through her issues is great - necessary, even, for the health of your relationship. Letting resentment build up because you get NOTHING during that time would negate all of that growth, though, and hopefully she is able to realize that and compromise a bit to find some ways to let you feel a bit freer and able to express yourself.
Do you have an idea of what kind of time frame you would be looking at if you did decide to just give her whatever time she needs? I mean, is she thinking she would be pretty much completely fine with everything if you would just give her some more time (a relatively small amount of time, I would think 3-6 months) or is she trying to push it off indefinitely?
For what it's worth, I think your situation is tough. I mean, mistakes have been made in the past which hasn't made this whole process easy for either of you. She really is working and trying, so how do you decide when to be selfish? It's difficult to say what is going to cause the most stress in the long run since you're both struggling right now. Finding a way to keep that stress somewhat balanced between the both of you so neither feels overwhelmed is going to take some give-and-take from both of you.