As a Roblox developer, it is currently too hard to change the default spawn system. Many games rely on custom spawning systems to better tailor player experiences. Whether this is spawning players close to their friends, near game objectives, away from dangerous areas, etc. spawning systems nicely elevate good games to great games.
However, modifying the Roblox spawn system is cumbersome. You cannot disable the default spawn system, you have to instead work around it (essentially waiting for Roblox to spawn you where it chooses and then quickly overriding that for a seamless effect). This is even acknowledged within the code of Roblox’s spawn with friends module: Spawn With Friends | Roblox Creator Documentation
I am not sure how this is internally set-up, but being able to modify the spawn system (such as changing the callback, ex: same way
MarketplaceService:ProcessReceipt is handled) would do tons towards increasing developer customization.
If Roblox is able to address this issue, it would improve my development experience because it would increase the ability to have full control over my experience.