So, I decided to take a look at both cities, via Google Maps, and simply compare the sheer number of buildings of at least 10 floors or of a minimum of 100 feet (or both) within Charlotte's Uptown and Nashville's downtown. Of note, the two areas are very similar in geographic size. From what I can determine, both are about 2.5 to 3.5 square miles.
Here is what I found. (Note: I have visited Uptown Charlotte three times and have a decent feel for it.)
Downtown Nashville counters with about 43 buildings of at least 10 floors or of a minimum of 100 feet (or both). Of this total, 11 were built prior to 1950. Of those 11, three — the Customs House, the Tennessee State Capitol and Union Station — derive about half their height from vertical elements (I did not count the First Baptist Church steeple or the Bridgestone Arena tower for this exercise).
Some other findings of note:
The overwhelming majority of Charlotte's tall buildings are located in Uptown (with a sprinkling outside that core). Conversely, Nashville has a noticeable number of structures 100 feet tall or taller in its Midtown and Vanderbilt/West End Corridor areas. Uptown Charlotte has twice as many buildings of 400 feet or taller (14 to seven) than does downtown Nashville. In contrast, Nashville has a significantly (I would almost say dramatically) better stock of vintage masonry buildings in the three- to seven-story range.
Admittedly, these numbers prove very little. But it was a fun exercise nonetheless. Now onto something more important — like, say, shopping for toiletries.