I just did a quick research on Komplete Kontrol and found out that it is software that can list all of your VSTis patches in one place. It appears to be aimed at the Kontrol Keyboards. IMHO if you don't have a Kontrol Keyboard you probably don't need this but YMMV. Note most DAWs will list VSTi patches and in many you can have a favorite listing.
If you are looking for different sounds then get the free Kontakt Player. There are a lot of free and to buy sounds patches for it. Just be very careful as although there are many sounds for it there are also many sounds that require the full version of Kontakt. Read the product requirements very carefully.