Grinding's never been the best way to level, it's just a time sink.
Ever play Kengo II for the PS2? It had a really awesome training system. It was a samurai duelling tournament fighter type game, and your guy had stats like "agility" and "strength" and "spirit", plus you could learn moves and string them into combos and all that. Quite neat.
Anyway, to get better at fighting, you didn't just fight all the time. To build agility, you'd run through a bamboo grove, using footwork to get into position to quickly slash through the stalks. For endurance, you'd stand under a waterfall. Each of these activities would boost your stats, but only in potential, so your speed attribute would be 325/438, where 325 was your actual stat, and 428 was what you'd "trained" it to through the minigames. When you actually fought practice bouts with other stuedents in your school, your actual stats caught up somewhat with your potential stats, depending on how you fought, so if you ran around a lot, you'd get a bigger boost to your agility and speed, whereas if you stood and used blocks, you'd build toughness and strength. Once you hit the ceiling, you'd never get better just from sparring, you'd have to go work out to raise your capabilities.
So instead of having to collect 8000 pieces of copper and make bushels and bushels of mugs, you could sit in your room with five different mugs from different makers and study them, then go to the library and read a book on mugs, then go to another guy's shop and watch him make some mugs, then drink some beer out of a mug, and then the actual workshop time you put in would be buffed by all the groundwork you laid earlier, learning about how mugs work and how they're made. Thus, a guy who's a mug expert and has made 50 mugs would make better mugs than a guy who rolled out of bed one morning, ordered a tractor trailer of metal and starting cranking out junk.