Hi, thanks for your input to this topic!
A new idea that we had how to solve this problem is allowing to create sweeps on runtime, i.e. that a user can e.g. return a list by ReadValues or CustomFunction and use another module to perform a sweep over this list that was just created during the measurement.
This way one would be free to create multiple lists or change them dynamically during a measurement. This would not only allow to solve the plotting issue (as the user can split lines for the module that is creating the different lists) but is also very helpful for many other use cases.
There is still some conceptual work to do here, but we are planning to work on it during an upcoming project until the end of the year.
Violin bars or error bars would then be possible as well. Although this seems to be a typical feature of the plot, we did not receive that many requests for it which is why we have processed other backlog items with higher priority so far. However, there might the chance to work on it next year as we have applied for a funded project where also improving data visualiziation is included.