Good Future IL Speedruns are done in both the original Mega CD and 2011 version, so I was wondering: Will there be a category for Good Future IL's here eventually?

As it currently stands, adding Good Future ILs to the already massive IL leaderboard would be a pain and it would cause the board to look like a total mess. Despite SRC being limited when it comes to having control and the customization of having things look the way we want them to: It is being looked into but keep in mind that it may take a while to find an approach that works well or not at all.

If anything is done regarding the addition of Good Future ILs then it will be noted.

If you want to run alternate Timezone IL's and submit them to a leaderboard, you can always do that with Sonic CD Restored: https://www.speedrun.com/scd_restored/levels

Again unfortunately the way it looks is limited, and when you see the grid for all the levels it only shows Sonic's best times, even if Sonic hasn't submitted a run. So there are a few Good Future IL's where Tails or Amy have submitted times that don't show up on the grid there. Instead of showing which character has the best (or any) time.

Restored supports the Origins Sonic CD RSDK file. (as well as the Steam and Mobile ones too of course, providing an identical experience with all)