An internally balanced engine requires a neutrally balanced harmonic dampener and TQ, these are sometimes called non-balanced or unbalanced. That said, if you had the wrong components on the engine, you would get a vibration relatively early in the RPM climb and it would get progressively worse.
Flat spots in the tires will be consistent and exhibit vibration early on and get more pronounced with an increase in speed.
So let's break this down, if you are getting a vibration through the steering wheel at idle, then it has to be a result of engine vibration transmitted through the K frame. That said, you are probably correct in that what you feel is normal. The steering column is rigidly mounted into the dash frame and any vibration in the car can be felt generally. So long as the vibration isnt horrible or violent you are probably good.