Depends on what you are crafting. If you are crafting NQ glamour items and furniture you can live without the items. If you are crafting level 70 0 or 1 star food you can probably live without a number of the skills (but you'll have to create your own rotation).
If you try to create 2 star or higher items you'll run into unpleasant problems. The level 50 cross class skills are entirely too required for crafting. SE really needs to fix the crafting cross class system, its a mess.