I'll chime in, if I may, as a SAHM with a former fabulous career that I loved, and eventually will want/need to return to.
It is hard! Just like everyone said, it is hard to have this discussion and implement it in real ways, unless each person is fully committed and each person has some built-in flexibility to their career (inherent flexibilty, I mean).
I actually talked to DH about this very thing YEARS before we had a baby! I did that because I knew, I just knew that it would be very difficult to juggle our two careers, due to inherent inflexibility and also due to DH's approach to life.
I also knew that if we remained a two career, two income family when we had kids that I'd basically be in charge of all things related to children's day care. And I really wasn't going to do that AND work my 40 plus hours.
So, we discussed...or rather I talked and talked and no solution was found. I'm a SAHM. I mostly enjoy it, but on at least one level (more really) I feel like it should have/could have worked out so that we could each have retained part of our career and each juggled parenting responsibilities a little more evenly.
Like I said, though, there are inherent inflexibilities so it's not all just on my husband's shoulders here. He was a bit of a jerk about it, but he also had some pretty difficult constraints to work within. So, I try to be understanding of that. It is what it is.
My advice would be, if you are really trying to transition your husband to the main breadwinner and you into a different career direction, then work on that. This other job might be a diversion from your intended path. But like another person said, there seems to be upsides to each decision. And that makes it tough. That's how it was with us. Since I made nearly as much as my DH, and liked my career, and could easily afford day care, there were upsides to continuing to work and upsides to being a SAHM. There was no clear answer and still isn't.