The splitting of the images i suggestest already some early in another thread, this will benefit in more space saving and in a better case of support the different boards.
I suggest in this case:
- Pi1-2
- Pi3 in 1 or 2 versions
- Pi zero in 1 or 2 versions
- Pi 4 only 1 image
Pi1-2 only for backward compatible, maybe just stop support and only provide old v9 the usage here go trending downward and its cheaper to buy a new pi these days. I think go forward here is a step backward of wasted energy and time.
For Pi3 there are possibly 2 options, provide a image with and without wireless from stock, but i think the better option is to provide just 1 image with wireless and bluetooth support from stock, the main reason here is simple.
Even the most ppl without the wireless on board will then mostly add wireless via external adapter later. So ship only 1 image here sounds like the best idea for me and minimize the support outcome again.
For the Pi Zero there is the only device where i see a benefit of 2 images, with and without wireless. The main reasons here are that an a zero every bit counts in performance, adding wireless or network is often not needed for Pi Zero's. So maybe the only Pi where its reasonable to provide and support 2 images.
The Pi4 specialy, i would only provide 1 single image. 64bit onyl,with 32bit libs for supporting old apps. But no need to split the images for 32 and 64 bit. To much support again, and since the Pi4 is the first Pi thats realy benefits from a 64 bit system, its more likly to be 1 of the os's that support 64bit Pi. There are also hacks for a 64bit kernel on a Pi3, since the Pi3 already have a 64bit prozessor, wich is only reportet false from Kernel, but the Pi3 not benefits from it at all. (Only needed for [mabe fun] and some special dev stuff)
But for the Pi4 there are much performance benefits in storage, speed, prozessor functionality, power consumtion, networking, and at not only the last the memory management.