hushed wyvern
TL;DR: Cut the price of brass torch holders down to 1 plate of brass instead of 2, require use of a hammer and chisel in the new recipe for them.
I like that making torch holders is restricted to the point where you can do proper metalworking. Having (good) permanent light sources is a big deal. I also really like how you're incentivized to explore in order to find aged torch holders you can re-use in your own builds; personally, I think they're rare enough that you can't get permanent light immediately, but common enough that it's a reasonable incentive to have you doing cave diving early on, when you're poorly equipped to handle it.
That said...torch holders are pretty expensive. 4 ingots of brass -- and the labor of hammering brass into plates, if you don't have a helve hammer yet -- for 1 permanently lit torch is a pretty steep price in the early game. Compare the cost of metal to that of lanterns. Said lanterns are limited in their production by beekeeping and mining for clear quartz, but they only require 1 metal plate. They also have the benefit of being easy to relocate, usable as an in-hand lightsource, and stronger than torch holders. So, in practice, you'll just use torches without holders in the very early game and use the aged torch holders you find while exploring until you can graduate to lanterns, which will then become your main light sources.
All in all, I feel like crafted torch holders are too expensive for the part of the game you'd ideally be using them in, which is before you've got beehives set up but after you've entered the copper age. I'd cut their price in half to 1 brass plate, and add a hammer and a chisel into the crafting table recipe for them, which you'd presumably need so you can shape the plate into a holder. (Obviously not consuming the hammer or chisel in the craft, just using up some durability on both.)
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