You can do that, yes, but is the demand so high for PvE servers? It's only a small portion of the people that prefer a PvE server over PvP, it will just end up with two servers with a highly unsymmetric population. The result should be obvious, one highly populated PvP server with the same unbearable lag issues as Elysium and one measly populated PvE server that will slowly die over time like the two Nost servers. Whereas dividing the realms based on community would have a greater benefit as I already explained in the OP.