I'm so glad you are back and loving HOD!

I have a 3 1/2 yo in LHTH, 7 1/2 yo in BHFHG, and just turned 11 yo in RTR. For us, it works best to have just the one child whose HOD book I am reading sit by me on the couch as I read, while the others are working on (or playing

) something else. My oldest ds can handle working independently at a table within earshot of me reading to my middle ds, and he enjoys catching stories as he works. If he were sitting very near us or could follow along in the book, he would not be getting his own work done, and worse, my middle ds would not be answering questions and being involved in the discussions he needs to be. My middle ds is much more confident answering questions without my oldest sitting right there. They are each other's best friends, but Riley can quickly see Wyatt will almost always give a better more detailed answer than he can - I'm glad there is not that comparison because he is off working.
When I am reading to my older ds, my middle ds is not within earshot because he is far too distracted. He is also distracting, being a loud child with many wiggles to get out.

So, my middle ds is either playing with our toddler on a totally different floor of our house when I am reading with my oldest ds, or else he is in the kitchen working at the table, while my oldest is in the living room on the couch with me, and the toddler is watching his educational video in another room. My oldest ds has started to orally narrate to my middle ds sometimes, just when it happens to work out, and that's been a fun way to have them swap history stories without my middle ds hearing it all.
My dc all love having me alone with them for school, and I love that they are all accurately placed and learning what they need to be for their ages and abilities. Especially with Biblical discussions. I have appreciated having one on one time with each of them. They share so much more, and are willing to talk through temptations, sins, and character goals more freely without others listening in. These times especially, I try to make very private. I feel so blessed that school goes so smoothly and happily most days. We love what we are learning.
As far as combining your younger 2 goes, it really depends on whether the 7 yo can handle Bigger Hearts. I'd check out the placement chart with just that child in mind, and if he's not ready for Bigger Hearts, I'd keep him right where he is and move up your next child to where that child places best, whether that would be BHFHG or PHFHG. If your oldest is ready for the independence in CTC, it is quite an independent program. After the first 2-4 weeks of school when you are really working on teaching how to do the boxes in the CTC guide, it should be very independent and not require much teaching time. As you said, the bulk of your teaching time will be Bigger Hearts. You could possibly go half-speed BHFHG with the 2 youngers, but leaping from LHFHG to BHFHG is a big leap. I hope something here helps. Please ask more questions if they arise, or if you check out the placement chart and have more to share about your 2 younger dc especially, we can chat through specifics too.
In Christ,
Julie