Try different things with the height, both extremes really. It has so much influence on the tone. I noticed it heavily in the bass side of my bridge Rebell Yell. Within one screw turn it felt like the bass response went from pop punk over classic rock to heavy metal, tone and feel wise.
You may get more power when you are close to the strings, but maybe you like the tone of the farther away setting better. So toy with that and maybe get a nice overdrive pedal (they can be fairly cheap), cause I recon that your problems are, as stated here before, are more related to the fact that you are now using a passive PU. I am absolutly certain that once you made that transition work, you will love the BKPs.
You just switched from a Toyota Corolla to a Ferrari. Totally different feel, but after a few near crashes youŽll adjust and rock that shite and everyones gonna be like: HOLY shite, that is amazing.