I think it makes total sense to combine your 3 and 5 yo, and LHTH will be a great way to do that.
![Very Happy :D](./images/smilies/icon_biggrin.gif)
It only takes around 20-30 minutes a day, which I have found is perfect, as the littles are vying for our attention as mamas anyway, and we are feeling like we are not truly able to give it to them - for me, LHTH was the perfect answer for that dilemma. It was fun, short, gave my little guy his "mommy time", and made me feel great about about the time I was giving him without it taking too much of me.
![Very Happy :D](./images/smilies/icon_biggrin.gif)
You can easily add in the right side of LHFHG for your 5 yo as time allows. By the time your 3 yo is nearing 5 yo, you could have a goal of having completed LHTH with the 2 of them, and having completed the right side "K" options for your nearing 7 yo. Then you can move on to LHFHG with either the first grade options or by utilizing the right side of Beyond, depending on where 7 yo dd is with her LA and math at that point. Then, 3 years later or so, you'd be able to begin your twins with LHTH, and your oldest duo would be very independent, your middle duo would be semi-independent, and your littles would be needing you just 30 minutes a day. We have 1 in RTR, 1 in Bigger Hearts, and 1 in LHTH - this mixture of guides has not been difficult to do, and it's actually really fun to be doing different guides with each of the boys - my teaching time is so varied, and each time with the boys feels "fresh" and unique from the other. HTH, but I think you have a good plan for your family here!
In Christ,
Julie