The biggest help Wi-Fi offers is the ability to update the Emulators regularly. And there are several updates which include tweaks, patches, and other performance improvements.yes, the Plus version has Wi-Fi and I am not sure what is the use of it? probably it can help in online multiplayer with friends
it has Bluetooth to connect other controllers but not wireless headphones
one other aspect is the Plus version supports PSP games.
rest all remains the same with price difference of 1.3k
Without networking, it becomes very difficult to update anything.
As you must be aware, Retro Games need Emulation, which needs Emulators. These handheld games have multiple Emulators and other software, including ROMs.