That's evil. Socialized Healthcare at its finest I like
You should also infect like 1 in 10 or 20 with an infectious disease, to keep a steady stream of business.
No, you don't do that at all. What kind of evil genius are you?
What you do is keep this up for a couple of decades until nobody has much of an immune system, any items of remove disease are long since gone (buy them up on the secondary market yourself if you have to), and most clerics or druids have completely forgotten they could prepare the spell, since there was never much of a need for it.
Meanwhile, with all the disease samples you've taken over the years from the most disease ridden areas of every major city on the continent, you selectively breed several super diseases, preferably ones with high wis drain. Then, one day you abruptly close up shop everywhere, simultaneously, have an artificer retain essence on your disease curing and agony draining equipment (which you were making with your proceeds - exponential growth), and release the plague. Actually, release the plague a week or so earlier, have it display symptoms about two weeks later and be infectious for the first two weeks. Oh, and make it resistant to magic, too. And have a false flag attack on own hospitals (ethergauts are rather unpopular), so as to deflect suspicion.
You now have a stockpile of craftable xp and gp that exceeds that of any dragon's hoard, the world's in shambles as the plagues you had stored up are now infecting the completely nonresistant populace, the high level characters will be blaming this on the ethergauts or trying to stop the spread of the disease, and the world will turn to you as a savior.
If your true nature is revealed, you have a lot of magical cutlery and the only stockpile of disease cures - a huge advantage in taking over the world by force.
If it isn't, you still have a lot of magical cutlery, the only stockpile of disease cures, a population that will welcome you taking over and stopping the plague, and your major opponents have been killed off or otherwise incapacitated.
If you want, you can go into the drug trade as well.