Hi, thanks for the feedback. I understand what you mean. In this mod, lead plates replace iron plates as an ingredient in sulfuric acid, 1 for 1. So, if you prefer to stick to the vanilla setup using iron, you can add sulfuric-acid
to the "Bypass recipes" setting for the Lead mod. Indeed, the "use" of iron in sulfuric acid is different than the use of lead, but it felt like a good way to replace some iron with lead.
It's possible that I'll revisit the "realism" aspect of some of these mods in the future and add (possibly optionally) a way to make some of the recipes feel a bit more realistic. Not really sure how this fits into plans currently. For now, my goal has generally been to respect the base vanilla feel of the game, sometimes moving a bit toward more realism.
Incidentally, regarding the contact process, I briefly considered it for the Noble Metals mod, but it felt a bit like overkill, especially since Pt isn't even the main catalyst used anymore. I will see if I can make it work nicely and consider adding it...