Adding the Planes of Power in to the original trilogy

[Fahn]

I like this Idea but several things to keep in mind.

PoT and PoK need to not exist for various reasons. One of those is; they were safe zones, absolutely nothing was even possible to get to kos there.

Also one thing you are not considering is itemization. If you do keep the current itemization, it will be really hard to break into. But once broken, old world content becomes trivial.

And if you change the itemization then you have to look at each encounter and change that. Spells aas, Lots of work there.

But /shrug after enough years of Velious, maybe this would be appealing. I did LOVE the raiding of PoP.