I think there is no silver bullet here. You need to use combination of things. I would try with PCoIP ADM templates. I would also try to upgrade the bandwidth if possible. Do you have any anti-virus in your VDI VM? Can you offload it to hosts? How did you create your image? Are you following best practices. Please refer this link - https://www.vmware.com/files/pdf/view/VMware-View-5-PCoIP-Network-Optimization-Guide.pdf