eBike technology explained

Hey everyone!

I've been doing a lot more trail riding lately on my hardtail eMTB, and it's got me thinking about all the tech packed into these things. Specifically, I'm curious about the different motor types – hub vs. mid-drive – and what makes one better for certain DIY modifications or even just general maintenance. What are your experiences with digging into the guts of your eBikes, and what's one piece of eBike tech you wish you understood better for DIY purposes?