from a gamedesign point of view, it all is the same for me, I actually preffered leveling my conster and resser in actual combat, because it is far less boring than pressing the process button every few seconds, but i wouldn't mind if leveling through tradeskilling was easier.

but from a lore point of view, it actually makes sense to have to level your intelligence and dexterity by doing activities in the world, not simply doing repetitive assembly line level work. someone constantly screwing the cap on a tube of toothpaste is not learning anything about scanning or constructing far more advanced items.