So here's muslin #2

I added an additional 1/2" to each side of the neck opening as planned. Gone is the gap between the edge of my shirt collar and the neckline of the jacket. Hooray! I also raised the back neckline 1/2" as well.

Thanks to Mrs. C for suggesting that I "dart out" the gap that made the jacket pull away from my chest. This looks so much better. A side benefit to making this adjustment is that now the jacket wants to hang closed. In this picture I don't have the jacket pinned closed. Before, the bottom of the jacket wanted to swing out when not buttoned.

Side view of the male bust adjustment! If you gals can have FBA's and SBA's I guess we guys can have the MBA!
I figured the dart to be about 3/8". After establishing its position in relationship to the other front dart, I marked it on my Swedish tracing paper and folded the dart out. Easy.
Here you also see where I've added 1/2" to the neckline. I simply tape on a scrap of paper and redraw the line. The Swedish tracing paper makes this a snap. Love the stuff!
To make the pattern lay flat I had to extend the dart quite far across the front. Hopefuly, this will keep the effect I'm after. New territory here.
This picture also shows the new neckline, which is now ever so slightly curved rather than straight.
Lastly, I trimmed 3/8" from the front / side seam, tapering up to the waistline. This has helped reduce the fullness at the hem without causing the back vents to pull open. I could have perhaps taken out more, but I've learned that most times a little adjustment is better than a huge one.
Ripping apart muslins and fudging them back together is hardly my favorite thing to do. I'll be very glad to put this step behind me. My fabric is prewashed, so it's time to cut this jacket out.