i have a suggestion to make a formula about crafting cooldowns and exp gained.
most of items are being crafted from same resources - alloys, metal parts, gunpowder, wood, junk etc. So why not to put it like this:
for example if you create item with 1 alloy, you are getting 20 minutes cooldown and 200 exp.
You craft combat armor, it needs 11 alloy, so from alloy part it is 11x20 minutes cooldown and 11x200 exp. (These numbers are total random of course)
Other materials have their own cooldowns and experience bonus for using them in crafting, and the total sum of exp and cooldown gained per item is the sum of these two things of all materials. Then it WOULD be fair for all professions :>