Welcome to the brave new world
The symbology in Europe gives some level of precedence to primary. That is not the case elsewhere definitely not in some areas of the USA where only SSR cover is available. NextGen will move to all ADS-B surveillance, in theory without any PSR or SSR. This lead will be followed by most of the rest of the world. All those heavy engineering turning antennae cost a lot to keep going.
I understand all the concerns as I started with a wax pencil and primary radar only. But I have watched controllers who have no primary selected on their displays to reduce the clutter successfully controlling extremely busy sectors.
Perhaps someone can say what the normal selection is for the radar 'picture' out of KL toward HCM