The problem with adding this as a migration target is that we would need to remove others, as the SE team strictly limits the number of targets and (without having hard numbers at hand) I don't believe that we get more networking questions then those that would be migrated to one of the present selections (SO, SU, DBA, U&L).
If you see a good(!) network engineering question, just flag for migration.
Adding it to the help page is a good idea though, and I've just done so.