Those are both good ideas. So the only way to die in the Balloon Fight stage is to get swallowed by the fish or get knocked upwards? Interesting.
I think that each Final Smash should be unique so I'm not too fond of the one you gave Ridley. I was thinking along the lines of a devastating screech that blurs the screen and rockets players off the stage. Or he releases Mother Brain and you control her for awhile. That would be quite intense.

Stage: Ghost House Montage

This level would consist of all the Ghost houses in the Mario Franchise. After awhile in one stage it would transition into the next Ghost House until the match is over. Maybe sidescrolling like Mushroomy Kingdom or just the best parts of each ghost house. Boos would be constant obstacles only seizing their attack while you look at them

Character: Midna

B - Portal: Sets up a portal in two locations on the stage. If you fall through the portal you reemerge in the other one. It can be set up either vertical or horizontal so that blasts from guns can also go through the portal. Disappears after awhile or if you set it up in a different location.

B^ - Warp: Midna Turns into particles and reforms at a higher location. Like Pikachu's quick attack you can choose which direction you move towards.

B> - Particle Toss: Midna grabs her opponent and juggles them through the air over her head as particles and slams them into the ground returning them to their solid state.

BV - Squeeze: Midna uses her magical orange hair to grab her opponent and squeeze them inflicting 10% damage each time. Opponent must tap buttons repeatedly to break free.

Final Smash - Taking center stage she bursts into particles that reform as the Mirror of Twilight. From the Mirror emerges the Six Sages. Midna reappears in her true form and the Sages transform into the magical blade that was used to try and restrain Ganondorf. She holds the sword up and the three great guardians that protect the land of Hyrule spiral out of the blade hitting all opponents off the screen. This would be a cut-scene final smash like Captain Falcon's.... seems a bit much but would be nifty to see.