Having said that I'd like to know if this small phone is a success or not. If no one buys it then maybe everyone is happy with phablets.
There are a couple niche small phones out there but they all insist on using a software keyboard that is _amazingly slow_. Typing is basically the thing that needs to work as fast as possible, otherwise it ruins the experience.
Almost no design is trying to acknowledge that the idea of a high-end small phone might be appealing to people (despite Apple having evidence with iPhone SE sales being decent enough).
In a world without all the apps, designing something almost ground up would make a lot of sense, since Android isn't meant to fit on such a small screen anymore.
I have some really weird wishes for a new phone. Something like the Nokia 104, but with 4G and wifi for tethering support. Oh, and a Google Authenticator app, for work.
If possible I would also like the option of having an Linux or Mac OS app for writing SMS messages on my laptop, so I can have a real keyboard.
For what you describe in your message above, have you thought about buying a laptop with built in SIM card support or alternately USB 4G SIM card modem?