I seem to notice that once my coffee has cooled down significantly, then I am able to taste a wider range of flavors. Am I the only one experiencing this, and is there a way to get different/more flavors while the beverage is still hot?
Interesting question. You are not alone when noticing flavor differences with different temperatures of coffee. When cupping coffee in a controlled lab situation for Quality Control purposes, I will often make multiple passes through the cups to taste the differences that are present as the coffee cools. Doing this tells me/us what we need to do while roasting to highlight/change the flavor profile of the roast.
The high acidity/brightness of a light roasted Kenya disappears as the cup cools. The darker roasted coffee that will show more "sweetness" at a high temp will show off more as it cools. These are but two examples. Other flavor characteristics that are found in roasted will definitely change as the coffee changes temp.
A lot of what you are tasting is perception. Here is a link to the key being how our taste buds translate it to our brain.
Once the coffee is roasted the only thing you can do to change the flavor profile of your coffee at high temperatures is changing the brewing method. All the variables in brewing will without a doubt change the flavors that you perceive. This will lead you to experimentation to find the flavors that you want to see.
Hope this helps..