I recently try your mod, and I have very big and overlapping ore ressources.
And I wish I could have an option, to select only one ore, to place drill.
Like coal overlapping with stone, an only select coal.
Thanks

Released an update that implements this feature. Enable it with a new option in miscellaneous settings.
Then the planner by default only covers the most common resource. Or when using additive selection mode (Shift+Left-click), use last normal selection with a single type of resource to pick the desired resource.