WetGeek It is a matter of taste. Personally I also use a manual provider and set the longitude and latitude in the config file.
For the color temperature I use the following: (basically it is more red during the day than the defaults and a little less red during the night than the defaults)
temp-day=4800
temp-night=3550
If you have never used this, at the beginning it is really weird as it gives the feeling the screen is turning orange, so you may want to start with softer values but once you're used to it, it is really more comfortable, especially if you have to spend hours working on the computer. I only suspend it when I watch movies (you can easily do that by right clicking on the applet icon).
