I have been looking for panniers for my bike all last night and haven't found anything I liked. This morning I was finishing a project for a buddy which gave me the idea of making my own panniers out of fiberglass. This brings me to my problem is what should I take into consideration when I am making a pannier for the rear of my bike. I am having trouble with ideas on how to have a lid for it and how much and where clearance. Overall my plan is just to get one big pocket and if I need more room I will make a sock for it with extra pockets. Once I get one perfect I'll make it out of carbon fiber if I find the need for more strength. Is there anything else I am missing to think of, I am open to any ideas.

Thank You
Max