Smithing is good but some little features are missing to make it very great.
At the beginning, I wasn't a fan of the learning process (tier by tier) but now with some practice of it I think it's a good idea, make sense and it's realistic. Actually, I didn't like it first because of the pommels ! Too many of them and too many times with different weapon type to learn. Make too slow to learn better weapons, especially axes and maces (1/2 handed).
When you learn an item on a certain type of weapon make it available on all of them, for pommels but for blades also, guards ... everything.
Also, there is a bug or something's going on wrong the learning process when you discover an item that you already have (very frustrating) and maybe worst, when you learn the item "none" ! Argh horrible ! Change that, please.
And finally, make possible for everybody, every player, to craft any weapon he wants. Go to a city with a blacksmith workshop in it, go inside (same interface that smithing, I guess) and order (like npc do) any weapon you want (type, pieces, size) at the price needed : 20k, 50k, 100k ... Not everybody likes smithing but I'm pretty sure all Bannerlord's players will pay a fortune to craft their dream weapons, and everybody would love this feature.