Why does everything take longer than I think it will? 
My wife calls me out on this all the time:
Me: "I'm doing some wiring tonight, should only take me a couple hours"
Wife: "yeah right, I'll see you tomorrow morning then"

Great progress so far. Interested in seeing how big of a CP you throw on there. I'm hoping it's not too big, 'cause I really like the slim shape of the cab already and something too mammoth will ruin the design IMO.
1. I decided to take a breather on the front door and come back to it fresh. The inside of my cabinet is 22.5", how much do I need to take off to get the door in there so it swings open. I was thinking maybe 1/8". Any thoughts?
Are you using a piano hinge for the door? And are you installing a coin door? (not that it relates to the doors size...just curious).
2. Regarding the front end - I haven't decided which way I am going on that. Any suggestions?
Mala is simple to setup, and uses low amounts of CPU resources, but it takes a bit of time to get it looking pretty.
Hyperspin is probably the prettiest, with video previews, scrolling game lists, but it's more CPU intensive. If you're going with a beefy computer, then I would recommend Hyperspin. It's nice.

3. Theme: Joust (I probably spent the equivalent in quarters on Joust as a kid as I am on this cabinet, so it seems appropriate). I ordered the Marquee from Game on Grafix and some bright red T-Molding from t-molding.com. I also ordered an 18" florescent light from Amazon. All of these should come in this week. Any suggestions on how to attach the Marquee to the cabinet? I see Happ has 10' marquee holder, but I am a bit tired of paying the crazy shipping charges ($10 if I don't have a minimum $25 order +$15 to ship).
People tend to get long Aluminum brackets from Home Depot (or whatever home improvement stores you have around), cut them to size and paint 'em black. It's cheap and the results are fine. You then need to put a small, unobstructed-to-light brace or lip behind your marquee plexi's so it can rest against or be sandwiched between.