My husband resisted re-opening up our relationship for a couple of years, and as soon as he realized there was somebody he liked, he warmed up to the idea in the space of a few hours, so I imagine your husband might do the same.
If you are OK with waiting for somebody to show him interest before you actively attempt to date.... is he LOOKING for interest? What do you think would qualify as such for him, somebody who wanted a one night stand or somebody who wanted to date him regularly? Are you OK with him looking, or do you feel stuck thinking that's not fair, because it is your turn?
Obvious problem with that is, lets say he starts having partners, and then you are "permitted" to date men, so you try dating and realize poly isn't right for you after all, then there's a whole other can of worms to deal with. Even worse if he starts finding partners and doesn't become OK with you dating men.
Hard place for you to be in. My limited and biased experience tells me that in general, men don't want to do the work. It is hard for them, so I don't blame them, but it sure is tiring when you know it needs to be done (and should be done, whether mono or poly). I personally am trying to focus on not "needing" my partner to do work/grow as a person, because I've found stressing how important that is to me has been having negative impact instead of being helpful.
I do think it's great that your husband seems to be good at being honest and open to the "best of his abilities" so try to appreciate that if you can, even if you wish he'd be able to actively identify what is really going on in his head and heart so you could get to the bottom of it and deal with the core issues.
Happiness will never come to those who fail to appreciate what they already have.