So even with the 3.2, you find you still have to use sport?
I'd have thought it would be quick enough without it? 
You never "have" to use it .. it is an option..

Sport button just does the same as kickdown switch, but more permanently, it holds the revs in each gear right to the limiter... with kickdown if you then ease off it will change up, with "S" it remains in the lower gear much longer ... which when "playing" in the twisties is beneficial as the sudden change of gear on easing off the throttle can be a tad hairy at times if kickdown is in control .... "S" prevents this.
"2" + "s" gives you, effectively a 2 geared car ... first to around 50, second to around 75, so the power goes down very quickly as minimum gear changes are involved, which is very different to being in "D"
The 3.2 is quick, but it is IMHO, more responsive under "S" as it is usually already in a lower gear.
All done at the expense of economy however !!! but the smile factor is good ...