This was discussed at length here - Manager Navigation Feedback
There were quite a lot of people against the idea of the change as well as for the change, hence the need to have the ability to choose between a flat structure or a grouped menu structure in order to please both sides and make it easy for novices using the program to start off with the flat structure which probably would work best for them and then as their business evolves gradually migrate over to the grouped structure.
The layout proposed by Ealfardan is the one that we ended up agreeing on largely. That is the people who wanted the change.
However, I suspect that it would require a fair bit of rewriting of the program as probably everything is linked based on the current flat structure. But hopefully one day this idea will be implemented as the current design is very inefficient space wise and I have several tabs that basically sit unused all year round such as the folders tab. A grouped structure largely based on Ealfardan’s design would work best for many businesses of all sizes as it groups menu and in theory access by department.