I am absolutely adoring the Megalith intro to Lightning. It's super informative and easy to get an intuition about thanks to the accompanying tutorial and also the Rizful cloud node. A lot of plain talk about routing nodes, in particular.

Also, these docs are the most engagingly-written that I have ever read in the btc space. Seriously. Whoever created these has a gift, I'm going to write them a fan letter if I can figure out where to send it. Maybe @rizful_com knows?