Renaissance Doublet/Jerkin - Part II: Problems

This is part of a series following my progress making a doublet. 
Renaissance Doublet/Jerkin - Part I: Getting Started
Renaissance Doublet/Jerkin - Part II: Problems
Renaissance Doublet/Jerkin - Part III: Buttons

ARGH!

A work in progress - needs buttons and front collar

All of the panels are sewn together and, I've run into a problem. I attempted to make the back one piece instead of two split down the middle. When I pinned together the interlining everything looked OK  However, now that I have all the layers together, it doesn't drape as much. There's excess fabric below the collar, above and between the shoulders, and in the lower back. One of the challenges of working alone with a mirror and without a form.

I also don't like how much of a length difference there is between the edges of the front and back panels. The web site I'm using as a reference suggests hiding it under the arm by aligning the bottom when you sew them together. I think I might rip the seam at the top of the longer panels, tuck in the excess to match, and resew the seam.

After pinning up the excess it looks like I have enough room to split the back panel in two, tuck and hem the excess fabric, and whip stitch the two back panels together.

After some alterations...

After some alterations

Well, splitting the back and taking in some slack helped, but there's still a slight pocket behind the collar. 

And there is a goofy notch in the collar at the back seam. I'm going to remove the integrated back collar and replace it with a one piece collar all around. I think that will look better and maybe the transition from the collar to the back will be more angular.

Goofy notch in collar

After even more alterations...
The integrated collar is gone and the back looks a lot better.

Now I just need to make a collar, buttons, buttonholes, epaulets for the shoulders, and eventually detachable sleeves.

Integrated collar removed