Pumping petrol at night might be a bit dangerous though, and the temperature difference between day and night in Malaysia isn't that big.

Actually high pressure can help with grip when cornering. A tyre can deform a lot when cornering, so much so that it slips from the rim (ok, you have to be cornering very, very hard). A more pumped up tyre should perform better. Also a with a higher pressure the car should feel more stable, react more direct to steering input. I think grip will only be compromised when the suspension can not keep up with the bumpiness of the road, so the tyre does not have any road contact. A less full tyre might be able to accommodate for the bumpiness and take in these bumps, thus maintaining better contact with the surface.

AFAIK a regular car tyre should not bulge under high pressure (as long as you still stay within the limits, usually I think 3 bar/300 kpa).

shouldn't the pressure depend also on the tyre profile?
low profile tyres shouldn't pump so much right?