Newhusband, all you should want for your wife is her happiness. Truly feel that and make it your life’s goal, then in return she will make your happiness her only focus. That’s the whole secret to shalom bayis — leave yourself out of the equasion. If you worry about yourself, you relieve her of the responsibility to do so. And if you stop focusing on her and her happiness then she will be forced to pick up the slack and think about herself before she thinks of you.
Halachically, if you have the means you are supposed to provide your wife with cleaning help. More money available? More cleaning help. Even more? A cook. Why do chazal even bother to discuss this topic? Probably because you are not the first nor will you be the last couple to have this discussion.
There is no good reason to deny your wife this request. Just because you’re not used to it? You moved OUT of your parents house, remember? Perhaps the two of you have different standards of cleanliness. If her standards are unsatisfactory to you, then get a cleaning lady to fill in the blanks. Don’t impose your way on her. If you don’t want to get a cleaning lady, then either roll up your own sleeves or be satisfied with the way the house is now. You can’t have it both ways. It will only get harder for her when she has a newborn so make peace with it now one way or another.
The time before your kids are born is special. Please don’t squander it arguing about “principles”. And just thank Hashem that you’re in a position that it’s not about the money. May it always be so for you!