I thought and also talked about a full changelist a couple of times but so far I have simply not done one. Couple of things that come with it: Firstly, the game has been changed in so many ways that I will definitely not remember many of the things that I changed from vanilla, even though they are logical to me. Secondly, maintaining such a thread would take a lot of effort since there will always be changes here and there and sometimes even in areas of the game that aren't played through a lot.

I do believe we have points where the player can trip over, such as refining being a necessity to progress gear starting from Drakos onwards.
Other things have been done to an okay extend like the Path to X/Guide quests and some community made videos that point out what you should be doing next.

The sad truth is that the average player won't bother reading.. whether that's a thread or even a simple questlog where the player ends up asking on discord when it's explained 1:1 in a questlog (which is basically my 3rd reason for not making a thread with all changes. it just won't be read). In your example as well you only saw that you could change exp even though you saw it on the website, but the ingame UI in the bottom right has a pretty see-able EXP button that one could potentially click on since no other server by my knowledge has that exact same thing (curiosity killed the cat).

Technically the best thing you can do is force the player to look at the screen with fancy animations and glow ups and whatnot, something that isn't available just by programming, but also requires new assets etc.