I agree, I think what bugged me the most about the Trapeze was how structured it's supposed to be, whereas my redyed PS1 just looks like a vintage school bag from the slouchyness. Also quite an interesting case with the Cabas ChYc, because from what I understand it's also supposed to be structured, but the sheepskin is just naturally saggy when compared to the stiffer textured leather.
At this point I'm very confident about redyeing bags to black, but I think it should be a super last resort kind of thing because 80% of the time I'd like to preserve as much as the original leather and finish as much as possible.