I have had various summer suits/jackets made up (from NYC, now in HK, much hotter and humid than NYC). My 100% wool jackets in weights that I can tolerate are too delicate and the fabric wears down too easily. They also don't have enough heft. I have found that the best wearing fabrics for a summer jacket are some kind of wool/silk/linen blend, or linen/wool. In addition, the type and weight of the canvas will also affect how warm the jacket wears.