I assume its gonna be allowed since way more people have access to 3D World now, but it has some game changes (Characters are faster (i think)) which makes it unfair for Wii U players

Why should a segmented run have an own leaderboard

No

why

I think pressing "Save + Continue" is a little bit faster because the game doesn't lag on the switch

I think it should be the same categorys from the original leaderboards, means Sunshine gets the categorys from the speedrun.com/sms leaderboard. Same with SM64 and SMG (If BLJs are patched in the SM64 Version it should be only 70 Star and 120 Star)