Allow insertion of Components into a Gallery, a Form, or a DataCard

[SaWu]

Please be so kind as to read my full post before responding.
Thank you for your consideration.

Currently, checked 2019-05-03, it is not possible to insert components into a gallery, a form, or a data card.
Also, forms, screens, tables etc are not allowed inside components.
By consequence this also disables the use of components in any scrollable context.
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/create-component

Please allow insertion of components into a a gallery, a form, or a data card.
I would already be happy to use components in their current state inside a data card.
I don't (yet) need support for a parent context of a component as I am fine with setting the component input properties by hand once and copying and, if necessary, copying and pasting.

Right now, I am using components only to:

1. simplify complicated formulas with several intermediate steps or reusable results (by using output properties for "temporary variables" for intermediate steps)
2. to make more customizable versions of the PullDown or ComboBox controls (e.g. Chevron Size, Spacing of Items in the expanded pulldown, ...)

Hence, I don't need more features or actual Form/Gallery/DataCard support but only the "plain" ability to actually insert the components inside something scrollable.