I think if you had posted this as a project here, you would have received many questions about which encoder you were using, which stick, which TV and you switch from XBOX to PC. I did Google you and saw that retroblast did a review on your (other) cab in 2005.
It looks neat. I've thought something similar, who hasn't? Putting a console in a cabinet. I think you are working against the stream though. Successful or not, Xbox/Microsoft has made an effort to take the game out to the arcade an bring it into the living room. You are trying to take that experience out of the living room and put into a box, in the basement. They've also made an effort to keep some of there console games off the PC, but I digress.
The game controllers are out of place as noted by others.
Where is the sync button for wireless players 3 & 4? Can all players be wireless?
I'd like to see more info about switching from players and audio from PC to xbox and back.
You should showcase scenarios where your analog buttons are a game changer. Play one game from a cold start showcasing this cabinet. PC or xbox. I've seen xbox live. Unless they have custom skinning, I know what to expect. I've made numerous posts to the software forum posting suggestions for PC games that give you that arcade experience. Some are better than others. It seems like everyone uses a few buttons too many.
$250 for fight stick. If you want buyers at that price, I think you'll have to show them more as to why its so much. Where is the value?
In general, things that allow people to charge for MAME are met quickly citations of MAME license and general disdain if not virtual pitchforks and torches.
I hope you do well in your endeavors. You may yield better results by selling the buttons, encoders, and your switching electronics than a whole cab, here at least. If nothing else, search x-arcade here to see the responsive given when someone wants more.
I think that is a neat cab design. You should consider reaching out to some of these cool cats that do the CNC cutting and working out a licensing deal on your cab design to be sold as flat-paks. $0.99 or even $1.99 to every Joe Blow that thinks he wants to build a cab like yours but never gets around to cutting wood. Monetize this or be content that someone got close enough by looking at the pictures.
+1 for request of PC and Monitor specs.
+1 on advice for the video. I mean you need a video, but it definitely looks like your trying to unload unused stock. Beyoncé that video ASAP or sooner!