I would like the ability to add custom properties and/or notes to the NetPath Service.
Yes. A hundred times yes. It'd also be nice to be able to tag Probes as well.
SolarWinds should make an internal company policy that states any new entity added to SolarWinds should always be added to the custom property editor before being released to the public. There's really no reason not to offer this feature for every entity type being monitored in SolarWinds.