I'm gonna list the two most common suggestions to fix stone spirits, and then add my own as the third.
1) Remove stone spirits from the entire game. Will suit most pvm'ers well, and some skillers who get seren spirits a lot because of low value on the rare drop table. While this might be the "easy" solution, it isn't what Mod Jack intented, and it will require a balancing look on all drop tables.
2) Replace all stone spirits with salvage. Have seen this suggested a lot. Will also suit most pvm'ers, but will make drop tables a bit stale with more of the same stuff, and insert a lot of cash into the economy.
3) Somehow make stone spirits more valueable.
Here is my list of changes to solve this:
Remove all f2p stone spirits from member monsters, member bosses and the rare drop table. The 1:1 conversion of the pre-rework ores/bars to stone spirits doesn't make sense with the reworked ore tiers. Then replace those with tier 60-90 stone spirits. (Luminite/runite from low level slayer monsters might be okay)
Nerf and balance the amount of stone spirits dropped. We simply have way too many of them. It devalues skilling profit, with the new mining rates it is no problem getting enough ores on the market. This will lower the supply and help stone spirits regain some value over time.
New effect: When mining instead of recieving an ore you consume a stone spirit and gain no ore, instead you get 50 % increased xp. If this is deemed too OP it can be 25 % instead. (Kinda like dwarven ramhammer effect and uses equivalent tiers of stone spirits to the ore you mine)
New effect: When smelting bars, there is a 25 % chance to consume a stone spirit and smelt 2 bars at once. (Uses equivalent tiers of stone spirits to the bars you smelt)
New effect: When smithing on anvils, every time you heat your smithing project, you consume a stone spirit for a 2,5 % xp boost and heat is lost 10 % slower. (Uses equivalent tiers of stone spirits to the bars you smith with)
You can now transmute 3 stone spirits into 1 stone spirit of the next tier, using divination and a small amount of energy of the same tier in divination.
You can now disassemble stone spirits. They should give a good rate of simple parts (increasing with tiers). Additionally tier 60-90 stone spirits have a rare chance of the following rare components:
Orichalcite/Drakolith: Dragonfire components
Necrite/Phasmatite: Undead components
Banite: Explosive components
Light animica: Seren components
Dark animica: Ancient components