ABAP CDS + OData + Fiori Smart Template; View parameters are not welcome?

Hi all,

I'm currently developing an application using a Smart Template and some CDS Views.

Since I need to perform some calculations (blame COEJ/COSR tables and their column-based periods!), I'm using view parameters and some artistry to get the job done.

So the top of my consumption view looks like this:

Problem is: the parameters are created as a separate Entity Set on the OData Service, which leads the Smart Template to restrict my choice of OData Collection to the parameters' Entity Set, while automatically defining the navigation to the Results Entity Set.

(if I remove the parameters and hardcode them on the select statement, I end up with a fully working List Report with all the data I expect to see)

This means that the Parameters' Entity Set will be used for the List Report (thus showing only the 3 parameters as columns of the Smart Table) and the Results' Entity Set will be used for the Object Page.

What I intended was to have Parameters show on the Smart Filter Bar (and included in the Variant Management control as well); working like filters, so to say.

Are there annotations I'm missing that can act as a workaround? I've seen the @Consumption.derivation ones but don't seem to fully understand them?

Am I asking for more than the Smart Template app can chew? Should I give up on the (very) limited ABAP CDS Views and move to HANA CDS Views for the calculations (plus an .xsodata)?

Thanks in advance,

Nuno