This isn't TBC and forth though is it? It's vanilla. I think an increased spawn time is the lesser of two evils here, you can't completely molest all the things you don't like about vanilla and create your own abomination of the game, as a wise man once said
Lotus being farmed is part of the game.
Vanilla is not some kind of a perfect game that shouldn't be tampered with. Just like any other expansion, it has major flaws which MUST be changed. Kronos team realized this at least partially, since they capped respec cost at 50g -- something that most of us love, while few people are whining about (fucking imbeciles). I don't see a reason why such an obviously flawed mechanic as Black Lotus shouldn't be changed as well. And making it a random drop is, imo, is as perfect a solution as it ever gonna get.