I missed having someplace to write your own code. SQL or JAVA would be really helpful . I am comparing this to what I have seen it Informatica PowerCenter or Business Objects.
The number of the functions available in the workbooks could be expanded. There is only so much one can perform with a limited set of functions. One tends to expect the functions available in MS Excel when you see a workbook like environment , especially if the target audience is non-tech savvy managers.
Could add some text features like regular expressions for text mining on data .
Employees with intermediate SQL and Hive knowledge can generate reports faster than using Datameer . It does have visualization tool but I don't think it is anything that cannot be accomplished by importing the data in Excel .