Actually most of the BLM questline is fixing that sort of thing. One way a BLM can gain power if through the void, but that is just one way. A good chunk of the THM questline is also about someone that failed to become a THM due to having a tiny aether pool (for lack of a better term), trying to find a way to increase it.
The reason why Black Magic and White magic are forbidden is because of the overuse of them. If you want to see a great example of it, go to North Shroud and run to the west exit by Coerthas. That was one of the sites during the War of the Magi. Both Black Magic and White Magic take aether from the lifestream, which kills the land in the process. That area in the North Shroud was a place that has not yet healed, and likely never will due to the Shard of Dalamud there. Even though in the game's storyline, Bahamut is no longer a threat, the corruption caused by the shard being there might have made the damage irreversible. The game never really says.
BLM being more forceful? Sure I could see a caster being more forceful, tearing aether from sources would be something a more malevolent, nefarious or even desperate BLM would do. The game has established since the beginning of 1.0 it's possible for people to channel power to each other (Making Yda's Limit Break in the 2.0 ending both possible and awesome, though Limit Breaks in XIV have always worked that way), so tearing power forcibly from an unwilling source would be something there in the Lore. IIRC Ultima Weapon was a warmachine working on that concept.
The reason why Black Magic and White magic are forbidden is because of the overuse of them. If you want to see a great example of it, go to North Shroud and run to the west exit by Coerthas. That was one of the sites during the War of the Magi. Both Black Magic and White Magic take aether from the lifestream, which kills the land in the process. That area in the North Shroud was a place that has not yet healed, and likely never will due to the Shard of Dalamud there. Even though in the game's storyline, Bahamut is no longer a threat, the corruption caused by the shard being there might have made the damage irreversible. The game never really says.
BLM being more forceful? Sure I could see a caster being more forceful, tearing aether from sources would be something a more malevolent, nefarious or even desperate BLM would do. The game has established since the beginning of 1.0 it's possible for people to channel power to each other (Making Yda's Limit Break in the 2.0 ending both possible and awesome, though Limit Breaks in XIV have always worked that way), so tearing power forcibly from an unwilling source would be something there in the Lore. IIRC Ultima Weapon was a warmachine working on that concept.
