I have used this type of rack and had no problems with it over many years use. The brake attachments are not weight bearing but serve to stop any rotation of the rack. The weight is taken by the U clamps around the fork and these can take a lot of weight so I wouldn't worry about not loading them with much weight.

https://www.crazyguyonabike.com/doc/...oc_id=6090&v=i

shows how I attached the rack with a U clamp. I would recommend you use these rather than the hose clamps you have shown in your pictures.