Here are some suggested places: http://mothership.sg/2016/08/4-new-places-to-enjoy-and-capture-the-ndp-2016-fireworks-display/ I wouldn't mind going somewhere near old airport road. Though it seemed like there is nothing much to do there, but the hawker fare along old airport road is quite nice (in my opinion). Would be nice to celebrate National Day with some local delights. :p https://sg.news.yahoo.com/12-places-catch-national-day-081521766.html A picnic at Kallang Riverside Park would be quite suitable for family outing I think. Kind of less visited but not sure if it will be crowded this time round.
Some of my friends plan to head out to Tanjong Rhu Promenade tomorrow. Apparently, there is a look-out tower near the stretch of water where you can enjoy fireworks with the National Stadium in the background. Sounds like a nice and fun idea :)