RB25DET S1 Tuning

Howdy, now I hope the I don't make an ass of myself and post this in the wrong place, but here goes...

As per title:

• RB25DET Series 1,
• Stage 1 modifications (CAT back, decat, HKS intake, uprate fuel pressure regulator, standard ECU (and standard state of tune I think), GTR FMIC)

The question (which I hope is complete enough):
After having some conversations about imports, I am led to believe that they run extra rich for safety
Q1) How true / to what extent is this?
Q2) (depeding on the answer to Q1) can I get the standard ECU remapped to be slightly less over-zealous with the beach-juice where it is not necessary and more appropriate when it *is* necesssary (say >50% throttle)
- so what kind of remap can be achieved on the standard ECU?

I bet that sounds like I talk a right load of beer cheese, but I can assure you that I don't ever waffle or over complicate my sentances.... ever...