Hi Cemr

I spec moldings based on the room type and ceiling height. That is, moldings should/can be more elaborate when the room calls for it, and simplified when it does not. Also, proportion trumps continuity in my opinion. Most of us have seen moldings (crown/base/casing) that look either too small or too large for a room, so using the same throughout doesnt always work when you have spaces with different ceiling heights and proportions, etc.

However, even with this variety, its usually quite easy to create a visual consistency from room to room

Steve