I like the concept of modular. I am a minimalist at heart, so prefer to have fewer, rather than more. Are you planning on using one basic design, which can modules detached/be multi-purpose or are you thinking a base design and then people buy modules they need?
For example, one day it may be a photography case, another for sports shoes.
Hello Anne-Laure Fayard , yes I have been sharing the sketches and concept, with really good feedback. My focus has been engaging with London Commuters, as that is the market I understand, can tap into and it's a painpoint for them. I have done this directly and through a blog post https://reachingaspiration.com/backpack-conscious-commuter/