> I feel there should be some sort of diagram possible that explains which industries and technologies pay more or less.

Is the entity you are selling your services to earning a large profit margin? If yes, then it is possible (but not guaranteed) for you to earn more. If not, then look elsewhere.

Generally, this situation happens in businesses that can scale with little to no marginal costs (software, media), can use governments to defend its property (intellectual property, land), and can be easily used as collateral (land) with which you can obtain leverage (money).