Explain the problem as you see it
Working with the current calendar and dates interface is difficult and inefficient. Using the command line to choose from a list of possible days, or typing @ and then the date is an inefficient way to get to a date. And then Weeks are a clunky interface for a calendar. I have to figure out what week contains this date. Better to be able to look over more than a week looking for dates.
Using Go To Date is more direct and efficient, but still not an optimal solution. At least whole months can be quickly scanned. Through Go to Date you can see when is the next Monday after the 15th.
Currently Go to Date is only accessible through Today. I almost never work in the Today view.
Why is this a problem for you?
I use Tana a lot for tasks and appointments set for particular dates. So all navigation of the calendar is difficult and inefficient, as described in the previous point.
Suggest a solution
Click the calendar icon on the far left (of the interface) to produce a 30 day calendar to the calendar icon's immediate right (a calendar larger than the small one which Go To Date produces)
Next choose date(s) by clicking on a single date, or shift-clicking on a range of contiguous dates, or command-clicking on several isolated dates.
The chosen dates then show up to the immediate right of the 30 day calendar, as nodes in a vertical list (like the current Tana interface). Whatever tasks, notes, events and/or appointment nodes for that date are listed under the date node (like current Tana).
This would be in place of the current interface of the Calendar that opens to show the Week nodes, which then open to show days that have tasks, notes, events and/or appointments.
This calendar interface is taken from OmniFocus 3, which has used it for some years. It's the most efficient and easy-to-use calendar interface I've seen.
A lesser solution would be to put Go To Date under Today in the far left column, so it could be accessed from anywhere, and/or make it accessible through the command line.