If you are pressed for time but still want to check out the falls, here is my suggestion! At the end of our spur of the moment trip to Syracuse in 2013, we stopped off at Niagara Falls before making the few hour trek back home. Even if you only have an hour or so, it is more than enough time to take in the beauty.
We visited the Ontario side of the falls (which I recommend) and it was beautiful! In our short two-hour visit, we headed to the Skylon Tower to get the best view one could ever ask for. There is parking available for a small fee at this location as well.
P.S: Did I mention heights make me nervous? How about a minute long glass elevator ride going up 775 ft up! (but it was pretty :))
Once we reached the top we spotted the Maid of the Mist heading into the falls. I would have loved to partake in that, but unfortunately driving home 6 hours soaked was not going to happen!
Before we set off on our journey home, we walked along the sidewalk for a closer look and admired the falls. Nature is amazing.