Good thinking about Power Armour training, Lycaeon. Removing a problem that leads to people looking for exploits is a very good way to discourage them from using exploits.
Damn it, I had another proposal, but forgot it. Oh well, I'll go with: Un-nerf the BB guns. They eject their ammo with a strength of 2 (whatever that means) and are pretty much incapable of doing anything. It may be OK for training, but hunters also insist on using them. While their force should be less than a pistol and it seems about consistent with what you usually have in mind when talking about them, some old designs could rival hunting rifles
http://en.wikipedia.org/wiki/Air_gun and I think a Stable would want them reasonably good.
I remember now, I wanted to talk about Prismatic smelter. While you added and re-balanced reactions to "make iron from ore" and so on, you did that the wrong way around. Those should be "smelt ... ore into bars" instead. That way ores will be processed properly, same as normal smelter AND scrap won't be a super-useful ore that gives 4 iron, 4 copper or 4 of some other metal.
While you're at it, please consider bumping the products of "smelt scrap" to at least guarantee an iron bar per job. Now from smelting it directly 10 times we get (on average) 20 bars, including 6 iron. Using scrap as ore guarantees 40 bars of whatever metal we want.
I believe these two suggestions together will re-balance scrap to be less OP, while still being useful.
> Scrap smelting should be a last alternative if your embark doesn't have iron, it shouldn't REPLACE iron vein mining. .__.
Wit the reaction to "make iron from ore" buffed to 4 bars it now does. It was previously at 1 bar, but would accept magnetite too. That's why the reactions should "smelt ore ..." and not "make metal from ore".
Also, scrap is not a bad ore IRL. It is collected, sorted and smelted. Besides, you want people to want to have a use for scrap, not just use some of it for scrap and leave the rest sitting around forever.