If you're leaning the low speed needle that little and temps shoot up, its your main metering needle (HSN) that needs to be opened up a little.
Also, try and engage the mid speed a little later so the LSN needle is in the spray bar a little longer. General rule when first adjusting the mid speed, is to move the LSN the same as the spray bar the same amount, in the same direction.
So if you retard the timing (lean the mid) by 1/12 then you should richen the LSN by 1/12 so that the spray bar, and LSN move together maintaining the same spacing. Then, once that is accomplished run it around, then bring it back in and first make sure your HSN is set so you are slightly rich up top, then lean out/richen your LSN last.
Should be able to get just as much punch out of the WS7II as the P5 without a noticeable difference anyway. You want to have enough bite own low to clear the jumps with minimal run; but at the same time you don't want the sucker to spin the crap out of the wheels on the slightest touch of the throttle either. Won't make you any faster
Anyways ... I don't own either so perhaps I'm just shooting the shit; but I know others who can pull as hard or harder than properly tuned P5's off the line without having to drop down a million teeth and drill the crud out of your clutch shoes.