That could easily work, BUT: I am not familiar with CFS, but downloading one of the planes I see an aircraft configuration (cfg file), with an entry for
[flight_tuning]
cruise_lift_scalar = 1.0
parasite_drag_scalar = 1.0
These control the scale factor for the total drag as discussed. Fiddle with the parasite drag scalar only, see how it works
This might provide some idea of what I am talking about:
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