Modes
Stage Hazards On/Off Button (Already programmed into the Wii U with 8-Player Smash )
Yes but I think it should go further than what's already available in 8-player smash. Let's call these modes for stages "Alpha Mode" and assume that all the 8-player stages assume their 8-player form. Then we'll add...
FD: Keeps its background from when the match starts and doesn't change it
Port Town Aero Drive: Remove all racers, add edges to the traveling portion, remove all other hitboxes except for the track while the stage is moving
Mushroom Kingdom U: Remove Nabbit, the spiky urchin, and the icicles
Halberd: Remove the claw
Skyloft: Remove the building hitboxes
Wii Fit Studio and Colosseum: Remove the walkoffs. They can just be ledges or there can be lava to keep the bottom boundary off-limits, just remove the walk-offs
Super Mario Maker: Only have one, competitive-friendly layout
Jungle Hijinks: Remove the Background
If we do all of that plus fix the boundaries on some stages (delfino while transitioning, revert DL back to its Melee boundaries) then I will be a happy boy