I am using my laptop to take notes in class and would like to use my android based e-ink tablet for quick handwriting and diagrams. What is a good way to get the content from the tablet to my vault as quickly and smoothly as possible? First-party sync? Note files pushed through Syncthing?
Try Remotely Save plug-in.
https://github.com/remotely-save/remotely-save
It syncs with Dropbox, Onedrive, S3 and WebDav. It has lots of settings like folders you can ignore, filetypes, etc. A number of experimental fearures that have worked when I tried them. You can set it to manually or automatically sync.
I’ve used it for my main vault using a self-hosted WebDav for over a year and been pleased with its performance. I make sure I keep a regular backup of the vault as well just in case.
I would imagine you could use the Excalidraw plugin as well for making handwritten notes and diagrams, too.