Things that don't explicitly add a skill or ability score improvement but another perk or quality of life or playstyle enhancement.
IE:
Extra pocket: adds X slots of extra inventory that scales up with QL, 10 being 1, 90 being 3. etc.
Scent cover/camouflage: Reduces the chance that aggressive creatures will engage you or reduces your own effective aggro range.
Comfortable padding: Reduces stamina and or energy loss from labor slightly
Armor plating/Lining: Adds a small amount of armor to an otherwise mundane piece of clothing, either so small it doesn't matter if it doesn't break or make the gild itself take on a durability value- and takes the slot with it when it breaks to make it fair and not a free slot exploit.
Herb treatment: Adds resistance against infection and or slightly increase healing rate of wounds.
Or even having a few rare gear piece specific gilds. or add gilding slots to things such as gloves for specific utility gilds as well. Much like how rings can only take gems.
Boot gilds:
one for waterproofing which lets you walk faster through shallows and marshes, another for cleats which lets you walk at a normal rate across rough ground/terrain like plowed fields.
Glove gilds:
Textured grip, speeds tool use slightly.
Protective coating/lining: Lowers rates of crab caresses, jellyfish stings, nettle burns, hedgehog quilled, etc.