The Malecon 2000 (Waterfront area that overlooks the Guayas River) in Guayaquil, Ecuador is definitely worth visiting. The area has been transformed into a very attractive place to stroll along the Guayas River, dine, sightsee and relax on a park bench.
You could visit the free Nahim Isaias Museum (take a look at the website, very nice) about 2 blocks from the waterfront. The upstairs portion of the museum offers some beautiful artwork to enjoy. No photos are allowed in the upper portion of the museum, but you can use your camera in the ground level portion of the museum.
Families with young children will enjoy the small train that the kids can ride on the upper level of the Malecon 2000 near McDonalds.
I only visited the area for a couple hours, but you can take boat rides and dine in nice restaurants on the waterfront. The area is very secure and not to worry about your safety.