Miner in the current meta is a very versatile Class that is not only used to increase the ore income but also to get Furnaces and Coal for free. The way this is done clearly shows that this was never intended and so I´m proposing this probably unpopular change: Miner The furnace is now Soulbound The placed Furnance smelts at double speed and doesn't require coal to work and only accessible by the owner however, it will disappear and drop the contents on changing classes like the alchemist stand. I believe these changes give back the meaning of the coal mine, as well as the necessity to collect cobblestone to craft furnaces, it´s still Minecraft after all and those tasks shouldn't be skipped by abusing a feature made in good faith. Please let me know what you think about the current miner and if the proposed change would be a good addition or not. PS: If you place the furnace in the mine while you are farming you would leave with approximately 8 iron, and in base you can smelt in both Ender and miner furnace 18 Iron per minute. It is as fast as 3 furnaces combined but you save time because you don't need to /kill and hope no one else picks up your stuff.
To be fair, no one complains about the quick coal/ furnace collection, it's a fun "exploit" which had sped up early game-prep considerably (in a good way). The coal mine, is still actively used after P1 if you'd ask me. The miner spam only happens at the start of the game and if you ask me, that's considerably fine. Coal mines in a lot of maps are still used for levelling (on maps such as Aftermath, Cherokee, Nature, ....), and on those maps, you will rarely see miner spams cause of the sheer cashflow of coal. If you'd ask me, taking away this minor bonus, would make gearing up early game even more boring. Less people would bother gearing up since it'd be a drag to get extra stuff done. More people would consider going around as leather. People gearing up has already dropped considerably, especially for solo players, so it'd be a bummer to take away a feature that clearly isn't hurting anyone.
If anything I would limit the coal you get to make people actually get coal and if soul bound atleast 3x as fast or be allowed to have two ender furnaces some how
Maybe switch that the Enderfurnace needs no Coal but the Soulbound Furnace does, that way it still looks like the Enderfurace is as good as the Miner.