Either 11 or 12 for everyone.

Sakura alt. 6 it looooooks like this.

black LIKE MY SOUL!

If you don't play Pink Guy, you don't play serious Guy ;) 
 
And hey, Sakura...

Black Ninja Ibuki. Sometimes I go for Dark Blue.
 
And.... Huh, I guess I only play Ibuki right now.
 
Used to use Sakura 10 (Dark Blue with Red Scarf ) in Vanilla.
 
I did set up everyone's color to something I liked after one boring afternoon with nothing better to do. Spend the whole day unlocking all the colors for everyone.

Yo, Boxer Original: 7, Alt. 1: 1, 4, 5, 8, 9, and Alt. 2: 2 are sexy. Really, every color in the Alt. 1 section are awesome.  
 
You get everything from Apollo Creed to some weird bubblegum pink outfit. Never mind the awful texturing and clipping (not as bad as Gouken's hat in Alt. 1...eugh) of the lower flap, Alt. 1 is fucking rad. 

No real preference, just sorta decide when i get the option, apart from HAVING to choose white gi Akuma, and bumblebee Cody. Obviously.

Usually the shady one, I think it's 11. Stylin'!

Ryu: color 2 for default, color 6 for Alt 1, color 8 for alt 2 
Rufus: color 8 for default, usually Color 7 for alt 1, color 8 for alt 2 
Guile: Color 9  
 
I pick color 11 a lot too. 

I use pink Adon, and either white or dark blue Cammy.

Pink or Purple or Dan Alternate 1 Green cuz Ninja Turtles!

I use color 4 for Dhalsim wearing Alt 3

I jump between 3,4, and 10 with Hakan. Maybe 11 if i'm in a mood. >:-(