In the downtown area near Suntec/Raffles city, it feels like everything at ground level is a mall (aside from a few historical buildings). Below ground level, there are extensive malls connecting large buildings in the area. As a pedestrian, it's nice to get out of the sun and skip the long waits at the crosswalks, but I did not relish all the time spent in a mall atmosphere.
I stayed in a different neighborhood for the second half of the trip and it was nice to get away from the glitzy, high-end malls of downtown. I ended up encountering even more malls though! They were smaller, older, and more run-down but they were numerous and packed in tight. Many of the construction sites I saw there were for new malls.
The malls do provide a refreshing air-conditioned space when it's unbearable outside, but it was hard for me to get excited about them other than that. If you will be traveling to Singapore soon and you don't enjoy Western malls, good luck in your planning.