The reason my shoes were so tight around my arch was the lacing which my shoes were delivered with. If you take notice of the Shoe shop lacing pictured below, you will see that when you tighten this lacing, it takes very little pressure before you make the lacing around your arch to tight. The solution is changing the lacing to the zigzag lacing, and leaving enough slack on the lower lacing.
It probably sounds weird that lacing should cause such problems. But give it a try.
I've also read of people leaving strings of leather in a | | formation above your arch, leaving a "channel" for air to escape through, which solved the problem.
