Looks good so far, but what you're gonna want to do to make it look nicer on the eye is give the character's a more in the front look maybe. One thing I might suggest would be to copy the colored characters, and place a layer behind the original and give it a motion blur going towards the left if it's the left pic (Haomaru) and right if it's to the right (Amakusa) This will really make the characters stand out and look dominating over the rest of the picture. Another good idea is to add some design features to it, cheesy can be good sometimes, it can really make a picture not look so bland. Lastly, for the background behind the b&w character portraits, what you might wanna try is first of all adding a nice black to some color gradient, then in the Effects look for Ocean Ripple, add a subtle ocean ripple, and it reallllly helps the eye look at the picture as a whole.
-Good Luck, if you want some ideas for cheesy design type of things or just some help with photoshop in general, just PM me or contact me via AIM s/n: CthulhuLA
-CthulhuLuke
PS: About the buttons, you are going to want to move the 7th neo geo styled button up, because otherwise you're going to find yourself moving your hand a lot more than you want to when you're playing Samurai Showdown 4 with the Neo Geo button style, I'll have my control panel pictures up sometime within the next few weeks, so that might give you an idea of what I'm talkin bout. (I'll probably have pics of my bro and I battling, doing those nice 14-hit combos, A B C, A B C mash mash mash.... etc) I'm a nerd