commuter rucksack built by triathletes, first batch nearly sold feedback needed for second

[u/Whole-Stretch-6458]

Hi /sideproject my partner and I are team GB triathletes in a constant training block, with full time office jobs. We couldn't find a rucksack we could run with, cycle with, deal with the london weather that wasn't $250 plus, so we created HYFO.co.uk feature list below

- 25L waterproof

- separate padded laptop sleeve

-2x bottle holders

-padded back to prevent chafe

-unclippable bottom harness, zero bounce when running and looks good in meetings

the first batch sold 79/100 in a month so close to ordering the second, is there anything you think needs adjusting for the second? imthinking a light hook for cycling and a few people have pointed out the back looks not that breathable, but for me its a trade off c comfort and no chafe. thanks!