Could be cool if it was one of those LED-lit etched acrylic signs. Could color-change, and you could do two right in front of each other to use two colors.
I'm jelly, man. Always wanted to do something like that!
Couple suggestions:
Make sure the height and tilt of the screen are just-right. If it's off by just a little, it could be uncomfortable to use. Ideally, I'd find an arcade and take some measurements for ones that you like.
Not sure what types of games you're planning to play, but would the Street Fighter 4 joystick-type pad have been something you could use, or maybe take apart and integrate?
Note: Not only does the screen "bezel" need to be tilted back, but doesn't the bottom panel need to be tilted to tilt the screen back?
Also, structurally, because all of the weight is at the top, you'll probably want to add at least one left-to-right and front-to-back structural wood bar about halfway up the body of the cabinet, or maybe a fixed "shelf". a weighted or double-thick panel on the bottom might be a good idea. Don't want it to be top-heavy, when your controls are cantilevered out from the front. If you're using the regular controllers on wires, then that is just a shelf to hold them when they are not being used, no big deal then...but I might anyways.
Casters, to make it mobile? It's going to be quite heavy.
http://www.richelieu.com/en/industrial-caster-20127200?fr=rec (make sure anything you choose would be heavy-duty enough.)
What are you going to build it out of/cover it with? Remember that pre-laminated MDF will be hard to cut without chipping. Not impossible, but hard.
How about a foot rail or a built in foot rest/panel with a rubber stair-tread?
Any way to build in a light gun and side holster?
If what you are putting into it will get warm, you could add active cooling (fans), or passive airflow. Either way, add an air intake slot at the bottom of the back panel of the compartment to draw in cool air, and an equal-sized air vent at the top of the back panel (avoid the top, as if it's taller than you, how often are you really going to dust it?
How about a built-in cup holder?[/yep, I'm an American.]