Can't answer on the hardware since I don't have the 7 , but keyboards are plenty around . I use gboard and remove network permissions ( jay GOS) why force a specific one on people? Just use the one you want.
Passwords keepassDX , MFA aegis.
Copy paste I havent thought about it guess what you compare to.
I'm no expert but webview is used anytime remote content is loaded I believe. Certainly you can open links in FF but webview is always there , and not so obvious things always load that way. Webview is baked inte the OS itself. No matter how much you degoogle.
Bromite had another webview based on chrome but that's all the alternative that exist as far as I know.
Chromium is still Foss. Google might have a stink and definitely tries to influence on the Foss part. But when it comes to vanadium I have no question about that everything is under a magnifying glass.
As I wrote elsewhere , all projects have their place and I do use FF, just not on android. I would be really happy if FF on mobile would be able to compete but I don't see that happening until we have full Linux phones (that actually does everything android does)
Don't get me wrong I do use Firefox myself , just not on android. The reason for using FF in onion project is that FF allows proxy needed for Tor. The aim is only privacy , security as a by product. As such they need to take a lot of measures against fingerprinting and remove functionality that others have. So all the projects have their own justification. But using tor browser as intended for daily use would be a real pain.
If you open a link in an app you are using the webview , gecko is not a webview.
As Firefox says: "Google does not allow a third party to implement the System WebView and the GeckoView API is not compatible with the WebView API in a very meaningful way unfortunately, so this is not possible."
Sandboxing is crap on Firefox (specially on android) . Google is really fucking good at security since they are well a huge multinational behemot. They know security. Security =/ privacy. When you are using android you are using Chrome webview no matter what browser you are using. So just piling on stuff instead of replacing things won't be a good security practice.
Also the Google parts are optional , you don't need Googles stuff to use chromium. Just like vanadium does.
If you are using Firefox on android you are using Firefox AND Chrome. Webview is chrome whatever browser you use. So using Firefox double the attack surface and weakens security since Firefox is not properly sandboxed.
Same recommendation as usual from me :) pepparmint OS , Debian base extra on top