Cant give you one because it is a thing of personal preference, I had several problems starting with the shoes so i replaced them and problem gone. But in your case you changed the whole bike including pedals.

Never used speedplay anyways but the only thing i can tell you is try to copy the cleat positioning as best as possible, some people gets the cleat all the way back, other ones use the ball of the feet over the pedals. Just remember the position of the ball of your feet in relation with the axle and try to adjust the same position in the speed play.

More options? Maybe the cranks in the new bike are longer?, maybe the floating in the speedplay is messing you up with the knee? The position in the bike was copied right from one bike to the other? Why don't try riding with the old pedals??