GIS: Filters on Categories

Dear all,

I am just doing some tests on maps and am a bit confused about filtering: I
can't seem to find a way to filter data on categories/dimensions other than
period and org unit, as I can in pivot tables and visualizer.

If this is not possible, that would pose a big problem to my data models, as I
prefer using few data elements and lots of dimensions in star schemes because of
flexibility reasons.

On the other hand the filter in GIS is on values (which is nice), although this
seems to be a major open discussion in pivot tables and visualizer. I would have
assumed that all three apps use the same OLAP-engine.

Question 1: Am I missing something? Is it possible to filter on user-dimensions?
Question 2: If no, will it be a big deal to enable filters on user dimensions in
the foreseeable future or do I have to remodel my star schemes, if I want to
offer GIS?

Best regards,