Double sharps and flats are rare in most of the music we play and yet, when working in Dorico, I am seeing them occasionally in my note entry and way too often in transposition, especially if there is a modulation to a new key. Instead of making the user select “Respell to avoid…”, Dorico should have that as a default. If there are chord symbols, the default should be no double sharps or flats and the notes associated with them should be transposed to the scale pattern of the chord symbol associated with it. This would make many of us really happy not to have to make so many fixes (like retransposing to a diminished second) to fix where a new key went to. At least we can do that, just more than we would like.
No, that should be an individual choice - as it would hide the harmonic progression or at least make it very difficult to understand.