As a Roblox developer, it is currently too hard to control the way physics of assemblies replicate to clients, e.g. when something moves on the server.
Many complex rigs containing several assemblies connected by constraints (8 assemblies for a four-wheeled car, of which several are not even visible, in my case) usually (and logically) take up more resources to replicate to other clients than a character, which is made of one assembly.
This effectively results in player characters other than the observing client one’s appearing jittery when a dozen of more complex rigs move in proximity; Even with InterpolationThrottling enabled.
If Roblox is able to address this issue, it would improve my development experience because it would allow us to create more dynamic experiences with more moving parts where the motion of said parts being smooth is cruicial.