Going straight to the point: 

1)  add connection type: Docker

This should not induce a lot of development since there is already an LXC connection type.

 

2)  add the ability to choose the bridge type of any virtual network:

+ VPP : Cisco has recently open-sourced the virtual switch/router which it uses with DPDK as a core part of some of its commercial virtual products.  Its performance should be unprecedented as compared to the current Linux bridge or even OvS. "VPP is also applicable to many architectures (x86, ARM, and PowerPC) and deployment environments (bare metal, VM, container)", according to Simon Dredge in FD.io Takes Over VPP and Unites with DPDK to Accelerate NFV Data Planes to Outright Nutty Speeds. 

+ OvS: not a priority IMHO.

Regards.

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