Steven,
IMHO I think you are right in this case to consider not adding more storys at this point. I think I would add the information for the new half storey to the existing storey that is above it. That way you would be looking down on the new 1/2 storey level below. To me this would make the most sense visually I think. Storeys are obviously important for visualization of the plans and determining what you want to show in relationship to each level and I have had the same experience as you in trying to add a story into the project part way through. Sometimes you just have to do it and spend the time to adjust all the related elements.
One thing you can do to help in adjusting stuff on the different levels is grouping (temporarily) all the elements on a level and then adjust things in section with grouping active.
Hope this helps a little.
Gerald
"The simplification of anything is always sensational" GKC
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