I am reasonably happy with blink, that it supports mosh is a big bonus as iPadOS likes to kill background tasks, but the screen refresh is not fast (the output is html based) and it doesn't deal well with split windowing.

I am aware of iSH, but as you say, its requires "using" the testflight system and while that might be ok for enthusiasts, it is nothing for the large audience. Obviously , as testflight is limited to 10k users.