The Scariest? The evilest? Which would you say had a better reason to be a baddie team then the others? Which team had a good soundtrack (within the games)? Which ones were the hardest to find and beat?

I would say the scariest team would have to be Team Aqua/Magma, they scared me shitless, after they stole the submarine I think when I shat 3 bricks and maybe pissed my pants a little.

The evilest I would have to say Team Rocket, all they wanted was to control the world, for no reason at all (No MAKE THE WORLD A PEACEFUL PLACE TO LIVE crap like Team Galactic)

I would have to say Team Galactic and Team Rocket had a great OST, just because Sinnoh and Johto were great regions.

I would have to say Team Magma/Aqua had given me the hardest trip in the entire world. It wasn't until I lucked into finding the undersea cave. Damn you Shoal Cave for being a trickster. lol

team magma and aqua definetly. although, in the distortion world and at spear pillar team galactic can get pretty creepy.

team galactic and rocket was evil, and Magma/Aqua were just trying to help other pokemon. Team Plasma is similar to M/A.

The Scariest? Team Galactic. Their leader is odd. Emotionless, yet evil and serious at the same time.

The evilest? Team Rocket. They actually wanted to take over the world and pulled a LOT of stunts.

Which would you say had a better reason to be a baddie team then the others? Rockets, as explained above. The others either wanted to recreate the universe to be peaceful or better for pokemon.

Which team had a good soundtrack (within the games)? Galactic and Plasma

Which ones were the hardest to find and beat? Magma/Aqua. They had complex and far away bases that were hidden.

The scariest? Team Rocket. They actually killed pokémon. For the lulz. And Cipher. They turn pokémon into emotionless fighting machines just because they want to rule the world.
The most evil? Team Rocket. Same reason why they're the scariest. They're also the only team that actually knows that they're evil. And Cipher. Same reason why they're the scariest.

Spoiler:

Best OST? I like 'em all.
Hardest to find? Team Magma/Aqua.
Hardest to beat? Cipher. Evice's pokemans are in the early 60's. Yours are probably in the early 50's.

Magma, Aqua, and PLasma were the scariest because they stood for more than "BWAHAHAHA"-type simplistic evil. However, most ruthless? Rocket.

Scariest? Team Jynx, 'nuff said.
Evilest? A Pichu. It just screams evil.

Pokemon trainer is the evilest he has the scariest powers! The power to be annoying.