I don't know if this has been suggested yet, but it's a good idea. Weapon Attributes would allow you to modify weapon stats other than damage, for example heat inflicted on opponent/ energy drained, or, for torsos, a way of increasing base heat/energy or resistance. In more detail:

To upgrade attributes, upgrade points are required. These are different from power points, and can be found (rarely) by opening item boxes in addition to the items, or by destroying mechs/ destroying warehouse-type buildings in campaign.

To upgrade weapons, an tab would be added to the fusion core menu that would lead to the attribute upgrader. Placing a weapon in the upgrader will display a range of attribute upgrade options. These cost a varying amount of upgrade points and increase different aspects of the weapon. A weapon's attributes are displayed with the weapon's stats. A limited amount of attributes can be applied to each weapon.

Vote & comment on this idea.