Not to be rude and just saying Im no admin here but how about i shatter your requests before the admins sees it. cos well the ans is going to be very similar either ways.(Well maybe less rude)
Spoiler
1) possibility for spectators to comunicate with the players during the game (is this a way to avoid spamming? I think it would be a valid way for newcomers to learn the basics or even just to point out an unnoticed mistake/cheat)
ANS: AKA Watcher's Chat? Im sorry the admins are not planning to do that any time soon (More like probably nvr since its been asked for like almost 20 times or more but nooooo).
2) Chat reporting (at least some) players actions[card draw,triggers]: this was a pretty useful thing in CC, you would not get penalized if you happened to be distracted for a moment and could easily spot extra draws of shady opponents with an already large handsize
Ans: As mentioned in the above comment this can be done already by holding down the q button. Thou u wont be able to check the cards that they checked thou but u will know if they extra drive or not.
3) adding an easier way to find player X or a way to know if said player is online atm (the general area is a gigantic cluster most of the time and the players name tend to be hard to discern)
Ans: Highly doubt this will be implemented into the game since the player counter is alr there and well u can just probably eye ball everyone in the map and just go to each map to find said person so admins aren't gonna be bothered by that.
4) some way to privately msg a specific player
Ans: Private chat is out of the question as mentioned above the admins aren't gonna bother abt such trivia things.
5) does the general chat only cover the specific area you're in? (example: a msg written by player x in the shop does not appear for people in another area) i'm not sure if this was my misunderstanding or if it is the actual case
Ans: Yes it does. If you are trying to ask for a map wide chat nope probably not gonna bother with that too am I right admins.
All in all I personally do wish for these updates myself but unfortunately I'm not a greatest programmer/Game Maker to be able to do myself not like the admins/Game maker who actually made CFA. So I can't really help you there but I guess all i can say is dun put yr hopes on requests and well just accept the game as it is :)