Well, well. It depends on how you play.

I'm not sure about that. Just last week, I leveled up four weapons from scratch to level 4, plus I leveled up 2 weapons from level 3 to level 4, plus 2 weapons from level 1 to level 3. It would have taken me about two months to achieve that result on my own.
Of course, leveling up to level 5 takes a long time, but you can level up both in the game and in the forge at the same time =)

However, in the last skirmish, I couldn't equip the hero with any weapons. Although I allowed weapons of the dynasty in the map settings. I suspect that this is again one of the limitations of Soul Forge. Either due to technical problems or as a penalty.