What I want is for enchantment of a weapon or armor to actually somehow modify the armor visually, not by just adding a shiny magic look, but by warping the metal, adding runes, etc., especially in a way that I can customize.
Here's an example. I think that adding enchantments should be a process of placing the appropriate runes where you want, and the material would naturally change as a result. Low-power enchantments would make minor changes to the weapon, maybe placing a single rune and not bending the metal at all), while higher-level enchantments would warp the steel of a sword, add spikes to my gloves, etc.
Here's something I envision.
http://img189.imageshack.us/img189/2346/weaponenchantments.png
{EDIT}
I just saw this thread: http://www.gamesas.com/index.php?/topic/1291091-all-bow-before-my-crafted-weapon/
and it gave me another idea. when you get to level 100, the weapons you enchant should include really epic effects, like having thunder boom when you score a critical hit with a sword, or having arrows leave a trail of ice behind them as they fly.