Detection/handling of BASIC, PAL/NTSC and memory size are actually things the Atari standard OS already does since 1982 so it runs with all these configurations. My "whish" is that coders who release new stuff try to take the time to detect/support these configuration. All you need is already there. Bits in an ATR header would of course be convenient, but more convenient is a program that also runs on different real HW configurations. And it would solve the ATR problem also.
Here I see the difference:
While the program may be able in some cases to detect essential (I'm avoiding the term 'basic' here ) requirements, what is the appropriate consequence? A message like 'Runs in 128k PAL only!'? Why an emulation based user should be forced to fiddle with settings and reboot, if the emulator could offer the needed environment before the application starts?
The benefit for real hardware users is not so apparent, but the documentation of the required settings is also a gain. All real users I know have some tags on their disk labels to indicate e.g. 'Super Boot/Old OS', 'Basic On', 'Speedy Off' etc. - It is advantageous if this information is attached to the disk image itself!
Even if all new productions inspect their starting conditions/switch them, what about the old ones? I bet most of the PAL users start 'Rescue on Fractalus' in PAL mode under emulation due to laziness (switching back and forth) or ignorance, while this game really deserves the NTSC frame rate.
Some conditions can be hard to detect e.g. should an application really examine if an high-speed-SIO is running which may have bad consequences for the experience? What kind of burden should the programmer take, just to ensure that his program runs under 'normal conditions'?
I'm not talking about abusing some bits in the ATR header, I have a new standard-format in my mind, which supports most of the environmental needs of an application. E.g. related disks form one image - so you shouldn't be able to separate side A & B while they form one application. Not only for ease of use but also with documentary and preserving aspects in mind.
I will start a poll now...