So it's come to my attention that Heat is a nice resource for people leveling their equipment in order to progress their characters, but after your equipment is maxed, then what? It goes to waste; it serves absolutely no purpose at that point.
Proposal: Create a system that converts excess Heat not used in upgrading equipment. Either make it convertable into CE or Crowns, be able to store it in a filling container of some kind for selling or using on another piece of equipment later, or something.
New "weapon/trinket" that would work like Heat Container. Although you have to equip it in weapon slot (or maybe trinket slot?), you can't attack with it. It gains heat just like any regular item but it won't level up. Everytime you are visiting Guildhall you can store heat from your Heat Container to Guild Forge. Guild Masters can use such stored heat to upgrade Guildhall, add decorations/pets, perhaps guild vendor and so on. I can imagine expirienced guild members with maxed equipment could form Heat Hunters Squads.