doogiePIM (PIM=Personal Information Manager) is designed around you so you start where you need to start. eg: If you're a coder and you need somewhere to store snippets of research and code whilst researching the web, then you would start with the Documents section whilst using the browser tabs.
If you're more into needing a way to organize the Events of the day, then you start at the Calendar.
doogiePIM isn't a tool to use for the sake of being there but a tool to use to assist with what you're a doing. Think of it as a Swiss Army Knife.
If you're already happy with your current set-up to manage your Gmail/Calendar then stick with that.
Don't try to fix something that isn't broken.