It would seem to me that to compensate for the fact that the album is now 3mm higher, I would consider utilizing the multi-record lever on the back that would literally raise the tone arm.
The way I would approach this to set your VTA de novo. As for the platter, yes the materials do make a difference. Everything has its own resonance. It can also make a difference if it is heavier (or lighter). By and large a heavier platter will improve inertia - the downsides being more weight on the bearing. And depending on the motor it may put some strain on that.
Another thing you can try (I have done this with many Technics platters) is to strip away the rubber on your metal platter. Before you start hit your platter with a spoon and try to remember the sound (or record it). Also weigh your platter. This stripping is a difficult job. But if you stick with it you will have bare metal. Again for fun hit it again with a spoon. It will ring even more. This is why metal platters have to have damping. Then with your platter upside down on a perfectly flat surface you pour in some epoxy - Gflex for choice. Wait for this to harden. What you will have left is the original platter with vastly better damping.
Metal platters have to have the ringing addressed. Replacement, Good Damping, or an Oyaide Butyl mat.