Everyone has an opinion, but since you asked . . .
I like your panel layout, but there's one thing I'd change - I'd put the VOR/Localizer Indicators on the left column of your "eight pack" and then slide everything else to the right one space. Personally, I'd rather have the Artificial Horizon in the middle, and the airspeed indicator closer to the center as well. More time will be spent looking at these and that's why I would move them over.
Just pure preference though . . .
I'm fitting the new Advanced Flight Systems AFS-3500 in my panel with an air-gizmo mounted Garmin 496 on the left. It will be hard to get the EFIS 100% centered and that's gonna drive me crazy!
The wife always said I was too particular!