1. Looks like you have a decent build process and a .travis.yml so some kind of CI setup. Very nice for a side project.
2. I love that it's open source, desktop, UI based. This has piqued my interest because the alternatives are either dated, proprietory and/or cloud or console based.
3. Download is rather big - 157Mb takes a while to download on my average speed internet and this might put people off. If it is Electron doing that maybe moving to https://nwjs.io/ would help?
4. Minor point, but it is odd to have an msi in a zip file. Just direct link to an msi would be nicer. Just giving people an msi would reduce friction.
5. The first screen says 'passphrase' but it is a bit confusing. What happens when I pick one. Am I locked out if I forget it. Can I continue without one? Would be nice to add a sentence explaining that.
6. I'm out of space if I add 3 categories. No scroll bar to help me. So have a think about the UI for that.
7. There is a bit of wasted space on the screen so have a think about:
* reduce wasted whitespace
* header fonts could be smaller
* sub categories could be in expanders, e.g. click an arrow to expand and see them.
9. This app does the basic budget thing of tracking expenses, but for people with multiple accounts, you want to have transactions across accounts, balances and reconciliation to make sure you haven't lost track of some expenditure. That is a lot of extra functionality and may not be for your target audience, so I leave that up to you.
10. Readme.md could do with some screenshots.
11. To finish on a positive - well done for making this and shipping it. It is not easy to make something like this alone. A lot of developers will have the grunt work of build pipelines and such things set up in their job and never think about setting it all up for themselves. Good stuff. I hope this project does well.