I’m surprised too about the lack of interest on this forum so far.
Regarding upgrades, I thought MS/Asobo has said pretty much every plane coded for 2020 will work in 2024, they just wouldn’t be able to take advantage of all the 2024 features. So you wouldn’t necessarily have to buy a new version.
Regarding GPS, it’s not listed in the work scope published on their website, but they have done it before (with their Grumman Goose) so it shouldn’t be very difficult to add and it seems to me it would help sales.