I was delighted to run across this post; I joined lesswrong so that I could reply to it!
There have been some pivotal changes since the push was made to adopt Esperanto as an IAL; perhaps the idea should be explored again.
One of these changes is AI. It should soon be possible to make an "AI friend" -- basically a glorified tablet, perhaps with a simple arm - that could serve as a baby monitor and speak to the infant in the IAL. The child would learn to speak the language effortlessly if it is well-designed and completely regular. The AI fr...
3Blue1Brown's (Grant Sanderson's) YouTube series on linear algebra does a phenomenal job of developing the intuition needed to understand the topic.