So after playing around with Tinkerer's Construct a little, I'm a bit thrown by balance.
TC tools can be made from better materials, giving built-in efficiency.
Many have built-in unbreaking as well.
While you cannot toss them at enchanting tables, you can craft (guaranteed) things like silk touch, or improved efficiency; you can add fortune, etc.
And things you can't get in vanilla: Auto smelt.
And then there's self repair (moss), or work-station repair (more materials); no XP cost to make, upgrade, or maintain. The tool never goes poof.
With no downside.
For balance reasons, can the default number of "extra slots" on tools be dropped to either 1 (normal play), or zero (ultra hard mode play); extra slots would come from paper, thaumium, or adding mineral blocks to buy slots.
Simply put: There is no reason to make a vanilla tool at all with this mod installed.
That alone tells me that there is a serious balance problem.
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Equally, the 2 to 1 bonus of using the smeltery results in no real reason to ever use a vanilla furnace, except to make one. Simply put, that bonus is too high. No, I don't know what to do for balancing that.
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By page 6, I now understand the point that people are misunderstanding about this. So let me try to be clear here:
1. Vanilla ores are in common supply. TiC adds even more ores. You are horribly over supplied with stuff.
Yet on top of that over supply, TiC adds ore doubling, and reduces the amount of materials needed for the equivalent item. A vanilla pick is 2 sticks and 3 ores; the equivalent TiC item is 2 sticks and 1 ore.
TiC does not need ore doubling.
2. The smeltery is a mechanic that adds tedium more than anything else. It basically acts as a giant "crafting table" made from a material that is a little harder than normal to find.
3. A TiC tool, defaults to 3 "add-on" slots, and can usually have two more; potentially three more. That is too many.
4. A high-end TiC tool is significantly better than anything you can get from vanilla tools except if you have the best possible vanilla enchantment books to use. The TiC tool repairs easier than the vanilla enchanted tool unless you use a questionable mechanic of the anvil that doesn't keep increasing the costs if it is renamed. (I don't know the exact method of replicating this, but apparently others do).
5. My point of this was to try to improve the balance of TiC as compared to vanilla, or in FTB packs like UHS. Not FTB packs like DireWolf.