I like the categories and budgets and I use them to keep track of my expenses. It’s all kind of pointless though since I’m not able to add incoming payments to those categories.
Use case: I buy something on Amazon, then get a (partial) refund. My categories and budgets should show what I actually paid, but just what my initial payment was.
Use case: I receive monies (let’s say because I sold an item on eBay) and want that money to count towards one of my budgets.
Possible solution: I understand why you would exclude incoming payments from the categories/budgets. Keep it that way by default, but let users pick a category for those payments, too. That would allow for greater flexibility on our end and shouldn’t be a fundamental change to your approach.