I read soo many forum posts that have players complaining about " Why isn't this spell in the game? or why isn't this domain in the game?, etc... " The player base seems to have forgotten that this is Early Access and there for nothing is complete. There are still more content, spells, classes, races, equipment, tweaks, etc.. still to be added. When all these things get added, fleshed out it will also quite possibly could fix a lot of balancing issues.... or it may not. We as players need to constantly remind ourselves that this is merely early access, not even alpha or beta. The tone of many of the thread posts speak as if this game were complete and polished.
Larian has stated that they're focusing on PHB, DMG, and MM material over later stuff, so it's very useful feedback to argue for implementing certain things from other books.
Early access isn't a separate thing from alpha or beta. Alpha or beta are measures of the completeness/bugginess of the game, while Early Access only means that consumers can buy the game early to play/test it. I'd characterize BG3 as currently in alpha
and EA, as there are significant features missing but it is still playable and mostly in working condition. Us EA players will probably never see the beta version of BG3 because Larian is saving Acts 2+ for full release.