The interface is too slow and clunky to enjoy making selections 25 times to make everything for a burial set. I often make an extra piece on the first time since if you click your selection and hit space too quick it'll do the previous selection.
#Let us make full sets at once while smithing
spare jolt
eternal tusk
(adding onto your idea)
If this happens to be impossible due to engine limitations, add a new item:
[Metal type] armour set (base, +1, +2,...)
Cost: same cost as making the pieces individually
Progress needed: same amount of progress. Could perhaps even withhold a bit under the banner of "You're making things easier so you get a bit less XP" (like how making full burial sets gives 5-10% more XP cause you need to make every piece)