I often think what kind of rewards dungeons could have which dont make clearing dungeons a necessity but would offer simple quality of life upgrades and this one came to my mind.
A small liftable and wood/coal/misc. fueled forge which you could haul with you while you're doing your mining trips so if you hit a "trash" ore node you could keep on smelting more bars for mine supports. This would decrease the amount of metal you need to haul with you for supports and let you keep on mining longer without breaking any mechanics or making it a necessity to have. Of course the quality these forges would have would always be quite low so that it won't be used for quality grinding.