Yes, all gems revert back to one template, with one strength, one color (purple) and one value. In the vanilla game there are 3 major gem groups, so I might raise it to that, but it is a minor issue, a lot of work, and needs tricks with "reaction class" and "has material product". Possible, but low on the list.
Besides, if you have magma or an excess of fuel (one of which, by the point you think about plated armor, you should definitely have), you can forge a shitload of plates from, let's say, copper. Now, the material of the plates does not matter, so if you use copper plates on welded mithril armor, it magically becomes welded mithril plated armor.
It's somewhat of an exploit, I feel mildly ashamed when I abuse it, but what the heck.
I am curious how to make it better. I could do one reaction for each metal, but that would spam the entire workshop full of mostly unneeded reactions. I can make the reaction accept "metal" in general, but then people have problems restricting what metal is used.
What would be a better system for upgrading armors and weapons ? Maybe using runes for both, instead of plates ? I could easily enable the platearmor in the entity file, it would allow plate-gauntlets as well, I would just raise the cost of bars for this high grade armor. But with the small amount of armor-tags in the raws I wouldnt know how to upgrade them to "runic platearmor". It would have no benefit, besides sounding/looking more dwarvish. Suggestions are, as always, welcome.
I also have a special project running by the side... looks like it is possible, and has definetly never been done before. I will let you know as soon as I have a working version of it.
@handfullofcheese: I know about this when a friendly gremlin is born, but the frogs... thats new. Will be fixed next version.
Exploding AmmoEDIT: Oh, completely forgot: I do have a second nice idea, that has never been done. EXPLODING AMMO. Syndrome bolts work, I can affect a creature with... lets say necrosis. Ok. But what if I give the creature a syndrome adding an interaction that allows one burst of undirected dust causing a syndrome? Arrow hits creature => creature releases undirected dust (cloud of about 20tile-radius) => dust affects all creatures nearby.
I can make explosions, releasing dragonfire-clouds, sleeping-powder bolts, transformation-into-sheeps (classic) or warpstone-bullets that have a chance of mutating/berserking enemies. Just imagine a goblin army, hit by ONE warpstone bullet, and 3 goblins mutate into abominations attacking their own army from within. HA, that will be fun, I really like that idea. Will result in more fun spells for mages as well.
Sadly, as far as I know, this cant be applied to siegeammo, but I can try.
EDIT2: And becaue I am totally not coding at all, and only sit on my bike and travel, and do not have too much time at night (sleep is for the weak) here some building designs:
Herbalist does work with special plants and direct "plant to item" reactions, leather manufactur makes sets and batches and you can select types of leather directly (normal, thin, hardened, scale, chitin, netherbark, llamelar, studded and so on), wood manufactur does the same for wood types (scrap, normal, smooth, ironbark, steeloak, nirnwood, shadewood, weirwood... yep, new wood types.), cloth manufactur does the same for clothing sets, batches and different cloth and silk types. summoning circle is drow-tech, allowing summoning of demons to fight for rewards, the temple of armok got a new design (feedback, good, bad?) and the bifrost/warpstone stuff get their own buildings. Bifrost Forge is currently a direct copy of the great magma forge with different color scheme, might be changed, but I like the look of it, and it does exactly the same, just with a different material. There is also a finishing forge now, to cold-hammer metals, the crucible does completely different things, and a mithril-forge (elven tech). The blast furnace and arc furnace I kicked out.