Most important 3 improvements suggested

this i agree. maybe @lubos can develop something to follow the system theme like the dark mode in Windows.

i believe this is already possible with your OS. for example, in Windows 10 you have display setting which allows you to make everything bigger upto 125%.

you can make a custom report. if you had searched the forum, @dcVest had already provided such a custom report here.

like many answers given in the past you can restrict your desktop users with a password. or you can download any free software available on the internet which locks applications.