I've been building https://carryless.org, a pack manager for people liking outdoor activities (and ultralight weight wheenies). It is focused on user experience, clean and simple UI. Open-source[1], free forever. Here's an example of one of my packs: https://carryless.org/p/Q22oPD3V

It's basically inspired by LighterPack[2], but LP is left abandoned and the UI is quite hard to work with, unfortunately.

[1]: https://github.com/eze-kiel/carryless

[2]: https://lighterpack.com/