Guang Zhouta is in Tianhe District, and my school happens to be in Tianhe District, so I can see it from the balcony. That is to say, many places in Guangzhou can directly see Guang Zhouta without obstacles.
But the best location is flower city square, which is the CBD of Guangzhou, so you can see not only the night view of Guang Zhouta, but also other great scenery.
Another best location is Pagoda. You can take a tram to Pagoda, which has not only the night view of Guang Zhouta, but also the excellent night view of Liede Bridge.
The picture below shows the night view and tram.