AFAIK this will create issues for you. The reason being is that not only are IP pools/SGTs assigned to them, but there are other configurations that could get messy. Some other items include associating the VNs as L2 handoff on the external border nodes (EBNs), VRF between the EBNs and Fusion Routers (FRs). The BGP address families on your EBNs will change and could create a re-provisioning nightmare. I would suggest not going down the path of potential VN name changes. Something else to consider is that 10 VNs may be a lot to manage. What I mean by this is that if hosts in VN1 need to talk to hosts in VNx then you will rely on a lot of manual route leaking at the FRs. Not sure of your design requirements, but I would suggest designing and segregating the VNs on what assets need cross talk. Then rely on CTS to manage east/west traffic between assets needing access to similar resources, etc. HTH!