In the end I used McCalls 6044 with a few modifications.
I cut the yoke, button band and pocket on the bias and instead of buttons I used pearl snaps.
I flat felled the sleeve seams following the instructions for the Negroni. If I make a long sleeved version I will cut each sleeve as one pieces and add a placket like the Negroni.
I wasn't quite ready to cut into really expensive fabric so I used some nice cotton that I think I bought at Spotlight on sale for $5 a metre.
There were a few raised eyebrows from Chris as I sewed this. I think he thought it might be a little too country for him, but he wore it all Christmas day and his eyes didn't twitch when I suggested making a few more. I think it might be time to cut into some nice Liberty!