Are there plans to add Baubles integration so that amulets and rings can just use the baubles slots? This would also solve the issues with grave mods dumping amulets on the ground.

The only issue then would be that you can only equip two rings without any other modded rings that support baubles. That'd also mean that you can't equip a lurker skin pouch and a focus pouch both at once, because they would both take a belt slot.

But I do think it was annoying at first figuring out how to equip them, and is probably further annoying that gravestones don't detect the Betweenland's equipments.

Well you already have to choose between rings, and bags with other mods installed. I was thinking this would be a good additional feature for larger mod packs that have lots of baubles and don't need another system for trinkets. Like you pointed out, Baubles can handle all of the betweenlands items and solve the gravestone issue.

Betweenlands equipment also needs other slots than those available in Baubles (e.g. where would you equip 3 amulets?). The fact that some gravestone mods don't pick up our items is not our fault, but that should no longer be a problem either way because M4thG33k gave us the code to add compat for TombManyGraves2 :).
I don't want to completely rule out compat with Baubles, it mostly depends on how easily it can be integrated.