There are all kind of tools out their to rename levels. Some free, some not. But I wanted to do it with Dynamo and excel.
Basically read all the levels that are in the project put them in Excel. Create a column for names and numbering, concatenate this and have dynamo put it back in Revit.
Here you see a screen grab from excel. The columns with Level name and Height are being filled by Dynamo from Revit.
The columns Number and Description are being filled by the user in excel. The column concatenate combines the previous two.
The sheet rename is where I let Dynamo read the new level names.
The dynamo nodes look like this: (click on the image)
One side note: it will ask you to rename the views as well.
You probably have to run the script twice: First get the data in, do excel magic, and the second time to put the names back in Revit.