I agree with the SuiteGL plug in route. It's actually not a large script effort assuming that something on the transaction will tell us which account to use. And if there are multiple income accounts that are possible, you may even need a custom record mapping table to keep track of all possibilities... although if there's only 2 or 3 options, for example, then perhaps only 2 or 3 custom fields on the item is needed. Just depends on the exact business scenario you're looking to solve. Feel free to reach out if need be.