The upper blank is awesome!
I agree that the lower blank can be tweaked if you are the fussy type (I certainly am).
For that much work for a slimline (which I Love) - I'd do some nice mods on the lower - I certainly don't need to suggest segmenting ideas to you, this is in your wheelhouse!
However, still an excellent pen (we're a fussy bunch aren't we).
EDIT: I love your knots! Not many can do these as good as you.