My Uncle, Aunt and cousin from the US visited me last weekend and our itinerary went as follows:
Day (Night 1):
Satay by the Bay
Walked half-way of the Bay Area which included the views of Marina Barrage, Super Trees, Gardens by the Bay and Marina Bay Sand
Day 2:
Bukit Timah Hill (Highest point of Singapore)
Little India (lunch and Deepavali street market)
Harborfrount and Sentosa
China Town
Arab Street (Mosque and Zam Zam)
Day 3:
Chill at home and Brunch in Toast box (Singapore Breakfast)
St. Joseph Institute (Temporary home for Novena Church Services on Sundays)
Remaining half of the Marina Bay (included Merlion, Esplanade, Fullerton Hotel and a walk along the river)

Merlion Park, 9 Oct 2016
Airport.
It felt like we were part of the Amazing Race. Tiring but most definitely enjoyable.