Do you typically attach the artwork directly to the MDF? Does the artwork come with an adhesive back, or do you use contact glue? I would assume that the vinyl material used these days is very durable so I am guessing that works by itself.
I've been dealing with metals for the CP so far. So my experience/opinion matters naught. I leave it to the more experienced.
If not, do you attach the artwork to the underside of acrylic and mount that to the MDF substrate?
No, never. The only time you would want to do that is if the art itself is part of the acrylic. eg printed on the reverse side. This is common for marquee's but I've never seen it for CPs.
If you have a separate sheet of art for the CP, it's to be affixed directly to the CP and the acrylic simply "floats" on top. The reason is simple, the acrylic will take abuse in an arcade setting so they're meant to be replace. Though I've never known an operator to actually replace the acrylic, but that's not the point. In your home, the acrylic will get some nasty scratches from the kids. You may find yourself wishing to replace said acrylic, bare acrylic is far easier to have fitted and installed than replicating, printing and installing the art to acrylic only to go through the cycle all over again.
Also, are the Illustrator/Photoshop templates out there to use for the design?
There is a template for the various mounts, like buttons, sticks, etc to ensure they're sized right. But an actual template? Never used one, they wouldn't match any of the sketches I drew up anyways. I can't recall where I downloaded my button templates.
I plan on finishing the MDF edges with T-Molding.
OK?....