You can achieve an extra 20 ft-lb with the following parts:

Mugen header
Good exhaust (mugen, amuse, Hks, etc)
K&N
Bigger throttle body (70mm)
Extrude Hone intake manifold
Adjustable fuel pressure regulator (dyno testing needed here to set it)

A light flywheel doesn't help increse Hp or torque but the car revs faster and is more fun on the city.

If I had to compromise I would go for the header and flywheel with K&N for improved city driving.

 

There is only one way at this point to easily increase the torque to respectable level, Final gear....
Seeems like you have some choices among three companies now. Spoon, ATS and recently Jets Integral-Kobe.
And the only good choice seems to be Jets'
Contact MG Racing, Giampiero is checking on it.
Spoon and Jets pieces are identical but price difference is around $1200??
With this upgrade your car will pull much harder at the low-rev range and it feels like you have 240+ hp car unlike before.
I have done ATS gear and I can attest easily that this is definitely the best mod I have done. But now Jet's much cheaper gears and possibly much easier installation than ATS, any one of you should seriously consider it before spending your hard earn money on header/exaust or even intake.
It seems like Japanese customers who had chance to test drive the Jet's demo car were all thoroughly impressed.
Sure with this upgrade you will lose the top-speed but what is your chance of always driving 130+?
Anyway other than going with supercharger this is the next best thing you can do to get some most bang for a buck.