Classic Crafting and Bank Inventory
When you craft something, since Classic does not pull from the bank like retail does how about this:
If an item does not have the materials available, disable craft button, grey out craft amount column
If an item has materials but some / all are in the bank, disable craft button, orange the craft amount column
If an item has materials and all are in bag, enable craft button, green the craft amount column
Jeff Prichard commented
Even just a settings option under Crafting settings with a check box of "Ignore bank inventory when crafting" would be a big help.