Will have to get it together really soon. I'll soon be at the point where my artwork is holding up the project.
My advice would be not to rush the artwork just because you want to finish the cab. The artwork is what makes or breaks the cab. IMHO it would be a waste of effort to build a nice cab and then just slap some generic artwork on it just to get it done.
Using the MAME logo seems a poor choice to me, insofar as you are building a cab to get the authentic look and feel of a real arcade cabinet and then give it a name that says 'Hey ! I'm a pretender !"
You don't have to do fancy artwork, a simple paint job, a nice color scheme, maybe some stripes, would go a long way towards making the cab looking good and unique.
A good example would be Rick's Titan XL build.

As for the artwork holding up the project : It took me more than 6 months of painting, sanding it down again, painting it again, etc. to get my cab's paintjob right. Was it worth it ? Absolutely.
You have a nice build going, with a little extra effort you can make it special.