If you bored with default KDE start menu. You can change it with lancelot start menu. It installed by default if you install KDE full install on archlinux. If it's not installed you can install these packages.
$sudo pacman -S kdeplasma-addons-applets-lancelot
Here's default KDE Start Menu:
To remove it and change it with lancelot. Right click on kde panel, then choose "panel options" then "panel settings". Then right click on start menu icon then remove it. After you remove it choose "add widget" then find lancelot launcher
Just drag n drop to panel. When done, you can customize the icon on it. Right click on lancelot menu, then change the icon that you like. :)
Ok that's it, here's the lancelot menu.
Lancelot themes follow kde desktop themes, so if you want to change lancelot looks/appearance just change the kde desktop themes.