Here Comes the Hammer
Location
Required Items
Rewards
What the allowance actually buys
One allowance here buys 263,120 EXP, which places it 2nd of the 3 Lv 70 Blacksmith tradecraft leves that record EXP. The best of them, Fire Sale, returns 693,190 EXP for the same allowance, 163% more.
Across that rung the return runs from 214,460 EXP to 693,190 EXP per allowance — 3 distinct figures spanning 223%, so the wrong pick leaves 478,730 EXP of the allowance unspent.
On whether to wait: the best Lv 72 Blacksmith tradecraft leve returns 954,450 EXP per allowance, 38% more than the best on this rung, while the Lv 68 rung behind tops out at 806,710 EXP.
At Lv 70 this data holds 27 leves paying EXP across 2 categories: the 24 Tradecraft ones average 433,208 EXP per allowance, the 3 Fieldcraft ones 1,302,824 EXP, which puts this leve 39% below its own category's average.
Gil ranks it differently: 1,387 gil per allowance is 3rd of 3 on the same rung against 2nd on EXP, with the best there paying 3,840 gil.
Deepgold Sledgehammer ×1 is a Lv 71 Blacksmith recipe, 2 steps deep through 2 intermediates, costing 14 units of raw material and 29 crystals.
Handing that in returns 18,794 EXP and 99 gil for every unit of raw material the order swallows, and the tree needs Blacksmith and Carpenter.