Torque S/C on 4.0 single vvti 6 speed

New here.
I'm in Brazil and just purchased a 2016 Toyota Sw4 (Fortuner) with 4.0 single vvti, 238HP.
It has a six speed automatic.
When driving around town and even on highway the rpm is always low, almost never see it over 2000 rpm.

Planning on supercharger and headers. Since it need to be imported and the final cost after custom duties will be double of the purchase price in US plus shipping I need to make sure I will be happy with the install.

Anyone have any experience with how low in the revs the supercharger is felt?
Will daily driving at my low revs make the investment a waste?
Will a smaller pulley make the S/C come in earlier?
I'm not about high rev HP, just low rev Torque.

The idea is Magnuson system.

Regards
Chris