I would like to see some sort of WAN mapping. Maybe this is in place and I'm just missing it, but NTM isn't automatically detecting WAN links. For example, I have a number of site-to-site VPNs. If I scan both devices NTM does not automatically display a link. When pulling SNMP data you should be able to see tunnels and destination networks, as well as local addresses. I presume that if I know I have a VPN, and I know the destination IP, and I know the IPs assigned to all devices then it should be possible to list where VPN connections exist.
Additionally, being able to see MPLS links would also be extremely useful. I'm not sure how to automatically build that topology, but that would also be helpful.