I don’t have too much advice, because I haven’t used MFW or A Gentle Feast. (Although I did try one MFW program and have looked at AGF.)
I have used some HOD. The fact that you can’t easily combine is the big negative for me too. Otherwise, I love HOD! I combined my two oldest when they were young elementary. They are only 20 months apart in age. We did Little Hearts, Beyond and Bigger. But we didn’t always do everything as written or check all the boxes. I know HOD’s website discourages this and I know why - it is based on skills and all kids are different. But we still got a lot out of it. And I know not everyone does it as written either.
Eventually I had two younger kids and I was stressed. There was no way I could possibly do 4 guides!
Now that I have one graduated, another in high school, and two elementary students, I’ve been considering doing Bigger with the younger ones and using the extensions. That’s what I would suggest. Maybe look into doing Little Hearts with your youngest and combine the other two, using the extensions for the oldest? Or wait another year for the youngest to do formal academics (there’s really no rush) and focus on the older two. I understand the HOD guides build in independence and the early guides are really the most parent intensive, but that doesn’t help us figure out how to get it done, does it? Lol
I hope some of this helped. I remember A Gentle Feast looking good, but I don’t remember the details.
If your kids seem to want more activities than book after book, take a look at Layers of Learning. It is a unit study for all ages, grades K-12. www.layers-of-learning.com
Let me know if you have any specific questions.