CONNECT Parametric helical stairs CE 11

I'm trying to build a parametric helix stair finally giving the parametric solids functionality a go but getting frustrated since it seems relevant functionality is missing or tools do not work as expected.

1. Have created a parametric wedge extruded solid to use as the stair tread.
2. Tried to use the "array parametric solid feature" "polar type" but unfortunately  a "Z delta" or "height delta" parameter is not present. It would be incredibly useful to introduce Z parameters to both the polar and rectangular array tools. That would allow to position each of the satir treads at an incremental height.
3. The only way then to achieve the intended result seems to be using the array "along path" method. The path then being a helix curve. 

3.1. Unfortunately the "helix curve" tool is not parametric and therefore it won't be possible to parametrically control the geometry of the stairs or enter the values when placing as a parametric cell.

3.1 Have nevertheless drawn a helix using the "helix curve" tool and then using it as the path for the array "along path" method with "rotate" ticked. I'm getting odd results with the treads rotating in an unpredictable fashion. (see image blue)

3.2 When using the same parametric solid, the same helix curve, and the same number of array elements with the standard (non-parametric) polar array tool the result is as expected  and the treads rotate consistently and remain horizontal. (See image red)

1. Why there is not a parametric solid helix tool? Are there plans to port the now legacy "helix feature" tool  as a parametric solid tool?

4.1 Have used the helix feature tool to draw the stair's helix stringers and then use the technology preview "associative extraction" to extract one of the helical edges as a curve to use for the array "along path" method. This actually allows to modify the parametric array path by changing the parameters of the "helix feature" but there are two big drawbacks: First I'm getting the unexpected result described in 3.1 and second the feature modeling is a "legacy" technology and I think doesn't allow to use local variables as inputs to control the parameters of the feature model or use as a parametric cell etc. Without a "parametric" helix solid tool or "parametric" helix curve ( with parameters controllable via local variables) I do not see a way to model the needed stair stringers, railings etc.

 The new parametric modeling, constraints tools are very promising and could be incredibly powerful but its functionality is still lacking a lot. While tools and  technologies (feature solids, Dimension Driven Design (DDD)  are now deemed as "legacy" , equivalent functionality hasn't been incorporated to the new parametric tools. Combining all the DDD's and feature solid modeling functionality under the new parametric modeling approach will bring endless possibilities.

I would appreciate any advice on how to achieve what I'm intending with the helix stairs without having to resort to GC. It may be I'm missing a workaround to these issues. 

Thanks

José