Here is a finished shirt made from the last pattern. This is worn over a close-fitting T-shirt and tucked into the trousers, as intended (but not as fitted):
The shirt looks and feels too tight, and restricts movement, especially when the arms are raised. Material is a cheap poly/cotton broadcloth from the now defunct Hancock Fabrics chain. Compared to the muslin mockup this has no stretch at all, which I think is contributing to the tightness.
I think arm motion might be freer with a more traditional sleeve with a lower cap height. However, this body is also too tight for me, so I think the next step should be to develop a more classically fitting pattern by grading this up a size.