Kiwi Next + Ublock

Go for Kiwi Next browser. Its being maintained.

Theres a tool named Android Universal Debloater. You don’t need root, only adb allowed. In the Debloater you will have the recommended appss to disable, but you can go forward.

Aurora recognize the apps normally. No need to unistall them. It will work just like the Play Store.

I don’t believe there’s any reliable option besides Samsung Pay, but it’s locked to Samsung devices. Privacy-wise, I’m not aware of any solution.

Removing the Play Store would not uninstall any other app. But why would you want to uninstall the apps and then install from Aurora? Aurora get its apps from the Play Store, but anonymously.