Just giving my opinions on these suggestions:
1. Shields, I agree but armor I do not. It would take to much space for all the new items and would be more of a hassle than fun. Also because of the many types of armor aswell + the blacksmith is focused around weapons, not armor. Shields though has been a teaser in the shop for a long time now so I'm pretty sure it's gonna be added.
2. There is a water bath in the store though not working of course. Having to temper the blade would be such a amazing addon to the experience. However, it's sad though that you don't actually use water to temper the blade but oil. I know right? I thought so too but then I watched series like Man at arms/Man at arms: Reforged. And it's true, its oil. So for this to be added, he would of changed the color from blue to like grey or black. Maybe making it so that if you temper the blade, they pay you more?
3. This game isn't about mining or farming. It's about a man/woman crafting weapons to be the best blacksmith there ever was. Idk why people keep believing that this game would be an adventure game where you fight monsters, mine and farm. It's not minecraft lol. And also real blacksmiths or old time blacksmiths never mined for ore or chopped wood unless it was for winter or warmth.
Maybe you can buy order statues instead of creating them. And instead of increasing the price of the items, you instead increase the speed in which customers arrive (which would be your reputation) and/or more famous customers with a more pricy order?
3.5 Can't you create those already? Like its not a official katana but if you create a two handed sword, I believe theres a variety which is thin and looks like a katana though with the non polished look like all of the other weapons, I might be wrong though. HOWEVER this game isn't set In the era where it's about Ninja's or Samurai's but instead it's set where demon's crawled surrounded by magic and where people believed dragons roamed. Or so it seems.
4. Fancy guards would of fit perfectly, for the other though, not so much. If you didn't know, people used to call them daggers, not knife's. A dagger is something you CUT with while a sword is something you SLICE with, so there doesn't need to be a Knife.
5. He could add so that if you level up to a certain point, you gain a new rank from that you started with all the way to master.
Amateur - Journeyman - Master
And for every rankup you gain a new perk like as a amateur you would only be able to make normal swords while as a journeyman you unlock shields and then as a master, then you can gain the knowledge to create engravings when asked for them, would of made more sense as it's sort of a master thing to do make engravings, usually fresh of the back blacksmiths wouldn't be able to do that.
6. What about instead of that, they can order multiple swords/hammers for a certain time and then you can deliver it. That's probably what you meant.
7. This is a little unnecessary as right now, if you upgrade from copper to tin and so forth, you don't really store anything, you just put them on the furnace and craft whatever and then give them to the customers, there isn't really a need for organizing anything OTHER than parts because the fastest way to do orders is having weapons on standby same thing with crafting items.
8. You don't create bows as a blacksmith, Maybe arrows instead?