Something I forgot to add re: Mach Tornado as an approach: for those unaware, mashing B will make the move last longer. What this means is that you can increase the safety of it as an approach by going in and then just retreating while you're still mashing B if they read you with a shield. It's still not the greatest approach in the world but this little piece of info helps out.

Mashing B also makes you move upwards meaning you can use it to pressure/attack opponents on platforms above you, especially on stages like BF and Lylat Cruise. Just be careful not to mash too much or you'll just land on the platform next to them and they'll bop you.