Okay, I didn't quite express myself correctly. Yes, I agree that completely eliminating something isn't good because it reduces the number of creatures for splitting and skeletons. So, by "eliminating," I meant what these checkboxes do: replacing them with equivalent objects.
And, in my opinion, it's better to have many mills and leprechauns than many useless objects.
It's better to make objects useful. Some people want to dig for the Grail, so let them dig, even if it takes 111 turns. If you don't put it in a tower or a conflux, it's not very effective. (It's not overpowered.) And so on, the fewer restrictions, the better, in my opinion.