Thanks for clarifying - i was assuming based on your description that you wanted an Edit UI for some kind of subsequence, not just a step (hence linking to the other post). You can accomplish that today via the workarounds listed in the link.
In our Company also hardware developer creates testsequences in teststand, so it would be nice, if there could be a small user interface to configure the values of the parameters for a subsequence. The solution could be, if they drag and drop a sequence into their main testsequence, a user interface pops up to configure the parameters for this subsequence. So it would be possible to restrict the values with a drop down menu or Radio Buttons or to give some graphical help to choose the right values.
Or maybe i could create something similar to the IVI sequences, where i can click on a button and a small editor window is opened.