About 50% of northern European skies during the winter half of the year are covered with dull somewhat boring grey stratus clouds. Surely it must be easier to depict textureless depth only clouds with no or few breaks. Breaking through solid or near solid cloud descending under a mile from the runway is harder and therefore far more interesting. Fluffy pretty cumulus with as much gap as cloud cover at the sim's current cloud maximum has room for improvement.
If broken stratus is difficult then solid would be just fine. Cumulus cannot be solid anyway, there can be no local cumulus updraughts without corresponding downdraughts (which increase the air temperature and so rapidly evaporate any cloud content).
