Missile weapons don't even work yet, and now they're going to start
Given two caveats, this is not a bad idea, although not one I think
is going to add much to the game.
(1) In real life, good medieval weapons didn't break all that often.
Mankind has always been into weapon research, and then as now, the
cutting edge (so to speak) of technology was in weapons. Knights
usually had one "battle" blade their whole career, and armor was
rarely damaged so badly that it couldn't be repaired. (Not so, alas
for the poor knights who wore the armor.) And it didn't take any
special knowledge to repair anything but plate armor; squires usually
repaired their knight's armor. Weapons weren't repaired. So having
a break percentage and requiring more than a minimal level of skill
to repair armor would be unrealistic. Which is not to say it wouldn't
be desirable. But it would be more realistic to greatly increase the
initial costs of weapons and armor, which are unrealisticly cheap in
(2) To keep breakage from being yet another "limit the warlords!!!"
rule in Olympia, breakage really ought to be applied to any objects
used with skills. Problem is, with the exception of fine cloaks for
Entertainment, there really aren't many. So implementing breakage is
just going to be an unfair burden on people who do battle,
entertainment, and sail (assuming you have wear on ships).
However, this could be remedied by having goods that were required for
most skills, i.e., Equestarian would require rope, Smithing would
require anvils, Forestry saws, Trading clay jars and so on.