Just as a proof of concept, here are a couple tutorials that we could link:
------- For the new player -------
WiseOldDog's guide
is not about gameplay itself, but about the time and mindset between games. A very valuable and short read.
arma473's 1v1 guide.
While it focusses on 1v1, a large majority generalizes to team games as well. A great first guide to read!
FtXCommando's guide to the economy,
and what that means for your gameplay. Very competently breaks down some of FAF's more obtuse systems to be much more transparent. (Not sure if all the numbers are still correct, but the general sentiment certainly is. Should check that, probably)
Heaven's Guide about generic build orders.
He made a lot of tutorials (see below) but this one specifically is great for new players as the first couple minutes of every game just matter so much.
------- For the intermediate player -------
Blackheart’s guide to improving forever.
It's mostly about mindset and meta-analysis but also has some great points about how your game, e.g. hotkeys, should be set up.
Heaven's full list of Tutorials.
60 tutorials in total covering a wide range of topics: Macro and micro advice. generic and specific build orders, faction overviews, etc. A great place to look after you have gathered some experience.
BRNKoINSANITY's "Weirdly Specific Tutorials for Supcom".
As the name implies, tutorials about niche topics. Sadly there are only four of them.
------- UI Mods and Game Setup -------
Blackheart’s guide to UI mods.
Some of this is debatable, but it's nonetheless valuable advice by one of the best players in the game.
nine2's guide to writing your own custom hotkeys,
if the build in ones are just not enough for you. Very technical and nothing a new player should concern themselves with. I just put it here for completeness sake.
------- Other stuff I'm not sure how to classify -------
Jagged Appliance's impromptu com drop tutorial on stream.
It's great stuff, but linking to individual tutorials like this in the client seems tedious. We could maybe make our own Youtube playlist with all the scattered pieces of information out there?