Spokes don't weigh much.
Many rims may be true, but are they really round?
IMHO, the hubs will make more difference than anything else. Phil Woods are the best. White Industries are probably next, and DT Swiss come along after that. A good set of hubs on a hand built wheel will out run many/most when coasting downhill. That's my measure of wheel efficiency.
Not related or affiliated, but I have been running Joe Young Wheels on my road bike, touring bike, and Seven Tandem for over 20 years. Never an issue, never a failure. I'm sure there are others.
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