I wouldn't go that route just yet.
Too many holes.
You can only size pipe from Friction or Velocity
No combined fixture units, Gases lb/hr, etc.
Revit doesn't calculate friction loss PAST a takeoff on a main, only past a actual break in the duct.
Critical path needs work.
I wouldn't recommend using these features for actual trusted data on a project, but I would recommend you learn how to do it on your own. I feel you'll learn it faster and remember it longer for when the factory gets it right.
A source, Fittings (with correct loss method parameters based off a material) connections (connectors with correct data).
I think the trickiest part is understanding the connectors, for redundancy or a return line.
"It's hardware that makes a machine fast. It's software that makes a fast machine slow."
