Joe,
I have built out a manhole layer that worked with the MACP/Nassco inspection form. We quickly realized it was too much for our needs and simplified it down to an easier to use form. I basically built the layer from scratch using the Nassco PACP manual and the codes that were used in there. One word of caution...if you are integrated with CUES or other CCTV software make sure you are using the same codes in GIS that are required of your inspection software. We ran into some issues with the integration between GIS and GNet.
As far as the workflow, once we got our manhole features set up the Collector workflow is super easy for the field crew and it works very well. We have both internal employees and contractors inspecting so we do not edit geometry within the inspection map. We handle that separately with a GPS map, Collector, and a Trimble R2.
Let me know if you have any specific questions, Id be glad to help out.
Cassidy