First of all I must say that I don't have any experience with poly-relationships. I am interested in a poly-relationship, but my girlfriend has made it very clear that she will not stay in a poly-relationship with me, and now it's kind of up to me to decide how we will go on.
I think your ideas sound very sensible and not at all "ridiculous".
I also think it's great that you could find a way out of this "crisis"-year together. I am also in a situation right now, where I actually absolutely don't want to leave my GF, but don't know how to handle my poly-tendencies.
I think it would be very important to just be very clear about what you want and what you don't want. If you bring this topic up, just reassure from the beginning on, that you are not interested in a "open/poly-relationship" and that you know yourself that there are certain limits and that you respect them.
My girlfriend for example is also a very "flirty" type and enjoys the attention she gets from men a lot. She also goes quite "far" with flirting, she dances with men etc., however she has quite strict limits and never lets any "sexual" contact (also not kissing) happen.
Even though she is absolutely
against the idea of a poly-amourous relationship, she's very open and easy with some other things, she even encouraged me to flirt with girls in the past, to meet girls, etc.
And apparently, your husband enjoys to flirt too? So there you have a good "ground" for discussion.
I think you should just not let any misunderstanding occur, and be very clear about everything and explicitely say that this is not about "opening" your relationship, and that you really don't have this intention.