The main draw of Mint for me was how it pulled all transactions from all of my financial institutions. Can GnuCash do that too or is it just a FOSS alternative of QuickBooks?
I tried cludging something together with email scraping once but it relied on too many online microservices (zapier etc) and I could never really stabilize it.
It's more complicated than just a spreadsheet but not as complicated as regular programming. You will want to learn general accounting practices like double entry bookkeeping to really understand how to use it though.
I've been checking YNAB out. I really like that it has an API subscribers can use.
One of my complaints is that it doesn't seem to have rule-based categorization, but I may just write a script (or find someone else's) that interacts with the API.
It could be that I misunderstood, but I mean something like Mint's feature where you can have it do something like this: "Always rename 'YRBNK PMT' as 'Your Bank Payment' and categorize as Credit Card Payment".
I've been using Rocket Money. It has mostly the same functionality as Mint, but seems to work a lot better. It also doesn't wait 5 days to notify me of deposits like Mint does.
Have several credit cards for your categories, and use the same checking account to autopay for all. View credit card statements for breakouts and ytd expenditure for each category.
Just a heads up that the Citi custom cash card gives you 5% back on the most spent category, great for rarely boosted categories like gas or groceries.
Seems to mesh really well with your budgeting method. Limited to one per person, but if you have anyone you trust to be an authorized user you can each have one to have two such categories.