FWIW, everytime you put a brand new set of tyres on, your steering will feel a bit lighter but slowly it'll be back to routine. That, to me, is just a new tyre thing. I experienced this on the Palio D when i switched from stock to NCT5 and then later to A-drives (which are a higher profile than the NCT5's). If you put on new GT3's on your Punto, i'm very sure you'll feel a lightened steering temporarily. Ofcourse 165 section feels lighter on the steering as the contact patch is less. So, Sat mate, unless you put on some Mahindra Jeep type tyres, you shouldn't really be worrying about steering feel etc etc. Cheers.