I like a kicker. Not sure if 1" or 2" is better for you. When I slip, my kicker keeps me from falling off the back. I would say angle is more important than height. Decide what angle you want you kicker and how far into the tray you want it. If you want 30* but only 2" into the tray you might want 1" kicker, but if you want 45* kicker you might need 2" kicker to get that angle. I don't see the height mattering as long as you get the slope you want. Figure the slope, then decide how far into the tray you want it, and buy the right height to make that slope and starting/ending point.
For me, my kicker is just to keep me from sliding off the back and lets me plant my foot when racing. I like my kicker about 4" long (width of my foot) and not very steep. I'm tall so when I have my back foot sideways it's almost at the edge of the boat and w/o a kicker a little slip and I'm gone.