As a Roblox developer, it is currently too hard to use players on a local server to test if server-sided or local content involved with groups work. I have been doing work for a group which requested the ability select which playermodel they wish to be. I was trying to test if the character change actually happened on the server by doing a local server with 2 players. The selection screen could not load any characters to pick from because it relied on Player:IsInGroup().
As you know, when you do a local test, it creates players with the name Player(x) and provides no IsInGroup data. I propose that, if able to be done, Studio receives Local Server settings so we can emulate being in specific groups and any functions which checks for declared groups will return true. This could also start the implementation of more Local Server features, as you cannot test if Player(x) owns a gamepass without setting up a buy prompt beforehand.
If Roblox is able to address this issue, it would improve my development experience because I would be able to figure out if my group-reliant scripts are working correctly and more-effectively use the Local Servers feature in Studio. I am unsure if this would more of a hindrance to developers, but it definitely has been a problem for me on a few occasions.
If you see any flaws with this or there IS already a bypass to this, please let me know.