Production speed is fantastically unimportant. Rarely are you crafting against time.
There are a lot of exceptions, though:
Food, booze, farming, mining, melting, wood cutting, siege operating, smoothing, sometimes masonry (blocks) and glass, and even bone bolt production. All of these are subject to exactly the same system, though quality sometimes isn't a factor.
Take mining for example. A masterwork miner could either mine slowly and extract 100% of resources (what a legendary miner does now but at the speed of a dabbler) or he could mine quickly and leave minimal material behind (mine at legendary speed, but only leave stone behind at the rate that a dabbling miner does). That not only solves a hauling problem that doesn't really add to the game, but it also closes up a bit of a logical disconnect in that if you don't want to haul stuff you're better off with crappy miners than good ones, because the good ones can't behave like crappy ones. Training up your miner would require them to slow down trying to mine at the higher recovery rate (a tradeoff) so you have to decide if you just want a bunch of crappy miner going along or if you want to invest time in skilling them up - a strategic decision.
This requires some changes to various aspects of the production system - either giving booze quality or finding some kind of trade-off to the skill, but it's a way to balance various features. For melting, low-skill furnace operators recover lower percentages than high-skill ones, but you need to invest in a fair amount of useless slag in order to get up to the higher percent. You need to decide if you have enough long-term need to make the investment - and strategic decisions by the player are almost universally good for this kind of game.
I don't know how woodcutting would balance or some of the others, but I'm sure they can be.