Not trying to save money or anything. Genuinely 78 + ceiling fan on low is most comfortable for me. Maybe it's the low humidity?
Some of it is certainly just tolerance or whether or not you're acclimated (heh) to it.
The AC removes the humidity when the AC runs.
But if you set your thermostat to 75F (24C), and your in-door air temperature is ≤75F with a humidity of 80%, the AC will do nothing for you because the temperature is "correct".
One needs a separate, stand alone dehumidifier with a hygrometer to deal with humidify independently of temperature.
Do a search for "whole house dehumidifier" for available products.
The situation you're describing can come up occasionally on mild days, but (unfortunately) Texas doesn't have many of those. It tends to go almost straight from winter to summer and vice versa.
On the rare occasion when I feel that it's too humid inside (a rainy day in spring or fall), I just turn on the AC for half an hour. It wouldn't be worth it to have a separate system for that.
Which will never ever happen during the daytime in Texas in the summer.
70 degrees F is my most comfortable indoor temp, and I try to let it go down to the 65-68 range in my bedroom for sleeping. This was true even when I lived in Los Angeles.
78 is uncomfortably hot even for lying around naked. 68 is far better for ordinary attire and activity.