I think you have it right, you can use the data between plated bullets and lead. However do not exchange data between Jacket and plated.
Most plated bullets are so thinly plated that you will get stripping of the plating if you drive them too fast, so stick with the lead data and you won't have that problem.
Some of the plated bullets do have thicker plating than others, so you may be able to drive them a little faster, but not much.
Jimmy K