I’m in your same situation with one major exception: I have two little dogs instead of two kids. And it’s a great life! Without kids, I’m able to do all the housework in one morning a week. I love cooking elaborate healthy meals and baking bread. The dogs are a bit of work (vet and grooming appointments, daily poop), but they make up for it by being wonderful companions instead of being exhausting children. I spend all the extra time chatting with friends daily, helping care for my young niece and nephew a few hours a week, caring for an extensive garden, reading a ton of good books, and doing stuff for extended family. My limited childcare work is by far the most draining and boring part of my week, even though I love those kids.
I don’t say all that to make you feel bad, but to emphasize that the key challenge in your life right now is probably the children, not FIRE. Your evenings will be filled the bedtime routine regardless of your work situation. Maybe things could feel better by focusing on finding ways to make the childcare simpler and more rewarding. And I agree with everyone that you need to find a way to split the housecleaning with your partner or outsource it. Like he could be in charge of vacuuming and dishes. Something that needs to happen often that you will never need to think about again. Otherwise you’re unfairly saddled with handling all the crap.