Something with a good work/life balance, it's all well and good to want to maximise your income but will you actually have the time to enjoy that money if you're always working? It would have to treat me like a human being, not a piece of disposable trash with zero rights; as is increasingly becoming the case with today's employment market.
It would also have to be something of genuine use to society, not one of these bullshit jobs the world wouldn't miss if it disappeared tomorrow, something of intrinsic value to society that I could be proud I did. Something that wouldn't violate my ethics, it wouldn't be a dream job if I morally disagreed with it.
I'm not one of these people who feel the need to earn lots of money. I don't care about oversized houses, sports cars that can only legally go the speed of every other car on the road or brand cult-ure. I don't need a swimming pool, I don't need to eat at fancy restaurants, I don't need diamonds or 50"+ televisions. I'd be quite happy earning a modest living so long as it covered my needs with some recreational flexibility.