Currently repairing weapons and armor involves buying the repair kits needed and typing /repair along with the location or the weapon/armor  ie: /repair righthand or /repair torso. What bothers me is realistically it shouldn't be possible to repair your gear while you have it equipped (how the heck would you be able to repair the back of your torso armor???).

What I think would work would be to repair armor much like you would craft it in the first place, the simple way would be to buy the needed repair kits and place one of those and the weapon/armor to be repair on a blacksmith bench and use the combine button the same way you would combine a sword blade with a hilt, a few moments later and the piece would be repaired however much based on skill and luck.

A more complex way would be having to include other items during the repair process, animal hides for leather armor, metal ingots for chainmail/knives/daggers, metal stocks for plate/swords/maces, maybe blacksmiths/leatherworkers could craft specific repair kits based on the type of armor. and again those kits/items would be combined with the piece at a blacksmith bench.