I ran ducts from my BRE like chin spoiler tie wrapped to the rotor dust shield. I found duct work really didn't have as much of an effect as good fluid, regularly changed.
I assume your fluid was from a fresh container? I had similar issues until I went to Motul RBF600. No ad for them, but the stuff solved a bunch of my issues.
I also had a brain adjustment with how I was using the brakes as well. Shorter period of time but harder on the pedal instead of longer easier.