VC with EX9200 has neither been recommended for use, nor 'officially' supported with any recent SW for last 2-3 years. Juniper made a decision at that time to stop using this feature. VC support is still in the SW, but do not plan to use it.
Your alternatives are either MC-LAG, or now EVPN-MPLS (BGP). I might recommend any new deployment to go with EVPN-MPLS, unless multicast is a current today requirement. Multicast support is limited at best with todays EVPN deployments, but improvements will be coming down the road. EVPN is a standards based method, and one I see many/most people moving to down the road.
MC-LAG is a more proven technology, been around for many years, but is not the most user friendly configuration. Use Space/ND along with new Conig Sync function does make greenfield deployment of MC-LAG much easier.
So bottom line, no VC, use MC-LAG or EVPN, both have dual control plane (VC had easy to use one, but maybe too many eggs in one basket?). MC-LAG with Space/ND and Config Sync/etc. does try and make the dual control plane configuration look like one. I suspect in the future similar improvements to EVPN configuration will occur - just takes time.
Do not confuse EVPN-MPLS/BGP with EVPN-VxLAN for which the latter is generally a DC Only use case. The most common use case for EVPN-MPLS/BGP is DCI. Not every Juniper product supports both versions of EVPN (and further improvements), so just make sure the product you intend to use supports the right type. Again in the future I would suspect all Juniper products will support both, especially seeing that the Routing and Switching products have gone back to common code base (to allow for common feature set) with 17.1.
Good selling.