I know Hanso has had great luck with EBH HH Pads (per his last post), but I have experiences the same as you. Even the pads I just put in.... they stop OK but not as well as the stock pads. This has been my experience with EBC pads on my current Rocket, My previous Rocket, a previous Daytona T595, a Sprint RS, etc.
It seems the stock pads give you the "sportbike" stopping power. Not sure who makes them for Triumph or more importantly, what the pad composition is.