Most people meet Singapore on the way somewhere else, and one night rarely does it justice. Three or four days lets you eat properly, walk the old neighbourhoods and see the gardens at dusk, and it is a gentle first stop that takes the edge off the long flight.
The island packs Chinese, Malay, Indian and Peranakan cultures into a short taxi ride. Mornings are best spent outside, in the Botanic Gardens or along the Southern Ridges; afternoons in museums and shophouse streets; evenings at the hawker centres.
The honest caveat is heat, humidity and cost. It is hot all year, rain arrives in sudden storms, and hotels and drinks are expensive. We plan outdoor time early and late, and pair Singapore with a beach in Bali, Malaysia or the Maldives.