I don’t know of anything super specific and to-the-point covering these specific topics, and I agree it’s a real need.
The entire data topic is one of the biggest sticking points and it’s already covered here (and elsewhere), but I’m not sure any of that is at the dead-simple, step-by-step level that can be parsed by someone who’s new to R and reproducible examples and also stressed out about the problem they’re trying to solve.
There are so many angles on the data problem that I think that itself confuses people. I agree that having some modular posts that take on a single small topic would be valuable.
If you’re game, you could start a couple of posts here in #meta for the topics that you’re envisioning and I can make them into wiki-posts so that others can collaborate!
ETA: posted at the same time as @mara 