Cool Can. Use one or not?

Some thoughts -
I agree the full flow will cure any "hot fuel" issues and keep the supply constant, which is the ultimate goal. I also agree it's a PITA to keep ice in. They do help, but as far as using a full flow with cool can, I would omit the can because you're simply going to end up with a chilly fuel tank.
I don't like where you're mounting it... If you have a tire failure the can is exposed. Either move it or put a debris shield aroudn it and the lines.
On your breathers... You need to get a hose that is oil and fuel compatible - That heater hose will soften and then can suck itself closed. Braided is best if you can afford it.