In a perfect world where everything was possible it only took time to make, a class that focused on crafting skills first and combat second. Instead of only 1 crafting crew skill and 2 others, you could take 2 crafting skills and 4 others for a total of 6 crew skills total. There would still be combat options like there are for the current classes, but just to a smaller degree with the focus on crafting items.
On a more real level, the ability to learn schematics from gear that is removed from the game, pre-2.0 gear, columni/rakata and the pvp gear that was removed; you could learn those from the training vendors. The missions skills (UWT/INV/DIP/TH) had the chance to drop schems for the cartel market armor/weapons from the packs that are no longer available.