By what mechanism can we use the Data Explorer to count our votes, say for electorate progress?
It can only be approximated, because the data needed literally does not exist in the system.
I'm not sure it should be anonymous to me as well
Agreed, I would like to see this, too!
However, the complexity of implementing such a thing right now isn't feasible. Perhaps in the future.
Currently, Data Explorer's data source is the publicly available data dump, which has anonymized votes for everyone.
To make it such that the system knows it's you logged in isn't that difficult to implement, but doing data retrieval while maintaining security of confidential data would add a lot of moving parts -- the anonymity of other users' confidential data must be maintained above all other concerns, so the simpler the better. Such a solution would require views of a database that necessarily has confidential data -- this is asking for trouble, saying nothing of storage and performance requirements/availability.
So, yes, I could maybe see this implemented down the road, but right now I'd say it's pretty much out of the question, or at least a very very low priority from a business perspective.