Sparky Linux is a Debian based distro. Sparky Linux MinimalGUI loaded with Openbox Desktop. So its performance is very fast. Very suitable for the netbook, low profile processors and old computers. The Sparky Linux MinimalGUI loaded with very minimum applications.
ObConf is the default tool to customize the theme. But it has no option to change the icons. The user can install another app called lxappearance and control the look and feel. Apply the following command to install the lxappearance tool;
sudo apt install lxapperance
The tool will appear at Applications > Settings > Customize Look and Feel