Forging your own tools before you strike the earth is a great compression algorithm -- it trades a little dwarven labor up front for precious embark points -- but if we forgo compression and look at broader strategies like skill distributions, I think we'll probably see information that is more likely to be helpful to newcomers on the Wiki. For example, I didn't realize woodcutting was such a waste of skill points, for example, and I've been playing since the 2D version. (I can hear the heavy optimizers now: "you haven't been playing very hard!")
After reading this thread, I started a fort last night and did the 'forge your picks/axes after embark" thing. Although it didn't take that long, it still delayed my starting industry. The metalsmith has to build 3 workshops, then complete 4 jobs to get that first pick. Maybe it's more useful if you're embarking on a glacier or something, but I like to hit the ground running.
So, some thoughts on forging your own tools.
I always do it, and I get a miner up and running by spring day 6 at the latest, so its not that slow.
Smelters require an architect and a mason to build, not a furnace operator or metal worker, so even with only one metalworking profession you can parallelize.
I always start with 1 charcoal to avoid the wood burning step. It only costs 10 points, and it means I don't have to deconstruct the wagon first (which seems to buy me more time before food spoils).
I build 2 smelters and run 1 for making coke from coal and the other for turning copper and tin into bronze. Since I need coke generation up and running first, the fact that I only have one architect doesn't slow me down at all, because by the time the second smelter is finished i have coke for someone to use to make bronze.
How fast you build a workshop is not dependent on skill in the required profession, so turning on masonry on a random dwarf is enough to get your smelters running as efficiently as a proficient mason (not that you wouldn't bring one most of the time anyway).
Bronze is the best weapon metal now, bar none. Well, gold is better, but you can't choose to forge out of that. Starting with copper and tin is cheaper than starting with iron. Win-win. (Steel is better for armor).
I don't pay for any furnace operating skill, i just turn it on for dwarves who have nothing better to be doing. Doesn't seem to be much of a time issue.
Thus, a minimal forge tools set-up following the above requires: 3 stone, 1 charcoal, copper, tin, 1 bit. coal, and an anvil. Forge 1 pick and 1 axe. More picks and axes can be had by bringing more copper and tin and more bituminous coal to make coke from.
I tend to bring 5 bit. coal, 3 ea. copper and tin, and forge 2 picks and 2 axes (saving 2 bronze for later).
In theory you could bring sets of 2 copper, 1 tin, and 1 bismuth for bismuth bronze smelting, but there have been reports of buggy behavior with smelting that on a non-magma smelter.
Edit: if you're going truly minimal, you only need one smelter, because you'll only have one 'make coke' action, and then one 'make bronze bars' action, which have to be sequential anyway. 2 smelters becomes more efficient the more bronze you plan on making.