Well, I'm putting great hopes in NWN 2 and Dragon Age, just in case TES V isn't going to be very good anymore without said paid content.
Actually enchanting and spellmaking are in the original game.
Aye, but only through the mage's guild, there are no "rogue" enchanters or spellmakers anywhere in Cyrodil. If you are a fighter and want a good custom enchanted weapon, you also have to be a good mage.
The effects selection is also very limited, to put it lightly.
Besides, with the third official mod titled "Wizard's Tower," my guess shouldn't be off by much.
(I rarely make predictions based on faith alone )