As for the shorter shoulder strap, I asked for this to have a 12-13" drop. There seems to be a difference with how Ignes measures their strap drops with how I measure my strap drops, though.
When the bag is lain flat and the strap adjusted above it as far as it can go (without being pulled taut), the strap drop is indeed around 13" -- just slightly longer, in fact:
When the strap drop is measured vertically, though, i.e. with the bag hanging by the strap that is now being pulled taut (which is how I always measure strap drops; the bag was only stuffed with paper when I took these measurements, BTW), the strap drop winds up much longer than I requested, at 15"++, almost 16":
The regular strap, on the other hand, has a lying-flat strap drop of about 16.5", and a hanging-vertically strap drop of around 18.5". The lengths of the straps themselves, from leather end to leather end (not including the hardware, which is quite large and therefore not insignificant either), are around 34.5" and 29" for the regular and shorter straps respectively.
When I actually wear the bag with the shorter strap, I definitely feel that it's far too similar to how the bag hangs with the regular strap. With the regular strap, the top of the bag hangs around the level of my hip. With the shorter strap, the bag hangs just a few inches higher, level with the top of my hipbone. There's virtually no difference this way, which kind of defeats the purpose of ordering two straps.
In asking for a 12-13" strap drop, I was expecting the top of the bag to hang a few inches above my waist and a few inches below my bust (almost somewhere right in between), similar to how the Treesje Asher or Magnolia hang with their shoulder straps (but maybe slightly longer). I based the strap drop on how another bag of mine with a 12" strap drop hangs, too, so I was expecting something pretty specific, and this wasn't it.
To demonstrate, here are (really crappy -- sorry!) mod pics of the regular strap and the shorter strap respectively:
(I'm about 5'5", and a UK size 16-18. Not sure what that translates to for US sizes, though I do know my US jeans/trousers size is 12-14.)
The red arrow is approximately where the top of the bag
should hang with a 12-13" strap drop:
I'm definitely sending in the shorter strap to be properly shortened, probably by at least 5" (taking the length to about 24" when not counting the hardware clips, which measure about 2" each). Should I play safer by asking for it to be shortened by 6 or 7" in length instead?
As for the puckered bottom piping on the back of the bag, I'm going to ask Maria to see if they can fix that without having to make a whole new bag. I kind of doubt that'll be possible, but...

I feel like it'll be a waste to trash this bag and create a new one from scratch, but do you guys think the puckered piping is something I ought to accept if it cannot be fixed? It
is on the back rather than the front, which is
some consolation. What would you guys do?