One thing you would probably want too see is their fireworks display. The fireworks show at Niagara Falls does these daily during the warmer months, usually beginning in late May with the last show scheduled around Thanksgiving. Outside of the summer months, the city still does fireworks on some days. These fireworks are often done to appear above Horseshoe Falls (which is likely why you will notice hotels located near Horseshoe Falls are more expensive, especially with rooms that have a view of the fireworks show at Niagara Falls.
The schedule is posted to their website: Niagara Falls Fireworks - Schedule & Best Views (niagarafallstourism.com)
There are also many videos posted on YouTube of what the fireworks show looks like: niagara falls fireworks - YouTube