Not to diss the effort but be upfront with what's required. You need to download install iTunes and iCloud, then you'll need to provide your apple username and password? Too sketchy for my taste, thanks.
I don't think that this will convince you but it's open source (https://github.com/altstoreio/AltStore), and you could a separate Apple ID specifically only for signing (https://faq.altstore.io/getting-started/troubleshooting-guid...). This is probably the least clunky way of doing it since that Apple still doesn't allow sideloading.