I am using multiplicity for 17 different computers.
If you mean you are concurrently connected to 17 different PCs via KVM, that is a lot...
I just reformated my primary and ever since I did, the bandwidth used has gone up a lot.
So Multiplicity has not fundamentally changed, your PC has, agreed?
There are settings you can experiment with if you have not already:
Stardock Product Lifecycle Manager