I want to try and make an old-fashioned oilcloth hat shaped like this Dutch Harbor Souwester Hat. The base material is woven cotton, which I would waterproof using oil and wax.

When picking a fabric does it matter if I pick something thin (100 gr/m2) like printed cotton or should I pick a heavier canvas (200 gr/m2) or even really heavy fabric (400 gr/m2)?

For firmness, I would use several layers when picking the thinner material. Can I just choose which fabric has the nicest print or should I worry about thin material wearing out much quicker?