Kenneth,
Moving the spi pole to windward:- I tried this around 10 years ago. At the time it seemed to give me the same speed with a lower angle.
However, the current spinnaker shapes have you going so fast that you are just wasting time adjusting things like this.

The sooner you can get motoring with the kite up the better.

Maybe it could provide a benefit in distance racing.

I wouldn't bother with it around the bouys.

Regards,
Phill

I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!