I agree that Larian are the DM implementing their own house rules, but at some liminal point when you change lots of rules, it stops being D&D and becomes something else entirely for better or worse. I don't claim to know exactly where that line is drawn, but Larian have crossed it.
+1 to this.
Also house rules are very often very table-related. And this having such a huge audience I think the better way to do it would be as close as possible to RAW and then let the modders have their way. 5e is damned popular, probably the most popular system out there right now.
I am btw fine with the advantage on heights. This is a valid DM decision for me (even tho its not raw). But completely reworking things like reactions or pimping spells with new effects is a little more in the direction of bad homebrew for me. I once talked to a DM that reworked the Inspiration in a way that would have made it exactly like the Lucky feat. It was a horrible idea.