Currently cluster have a several problems.
1, they're surprisingly difficult to select in the viewport.
2, when created, they're zero'd out.
3, when you bake their pivot, they move in mysterious ways.
4, they're not procedural.
5 the 'relative' tick box is difficult to predict when used in hierarchies, and practically non-editable once created (because it messes up and jumps about unpredicatbly, especially on animated objects).
Personally i would recommend having more options such as making it a child of the object it is assigned to. Making it possible to zero out, bake pivot and have its transforms in the channel box from the get go. It should be easily editable and completely stable. An addition of 'cluster in group' or 'cluster under locator' would be useful too.
Pretty basic fundamental stuff that needs sorting out.
