hmmm... i have the bowler in black deerskin and it is holding up very well -i know exactly how you feel on your concerns on the top caving in a bit
your best bet is to keep from "smushing" it too much when carrying under the shoulder (b/c the bowler is quite wide, and tends to indent inwards after being carried too much in this manner
another VERY useful tip i got from the ladies here is to keep it stuffed when storing, which will help retain its shape in the long run -so basically, when you're not using it, STUFF it back up like when you opened the box... it's a pain in the butt, but taking that couple of minutes to do so will definetly keep your bag in better looking shape in the long run
can't think of anything else! hope that helps... and congrats!! the luxe bowler is literally one of my FAVORITE bags!