Completely agree @itay. I also think that the map starting position and zoom factor should be customizable on FME server and not just based on the Configuration settings of the Geometry parameter in Workbench. It would be nice if these, plus window default size settings were able to be set in an FME Server App as well.
I'm actually unable to change the size of the 'Geometry Picker' sub window in my browser. I think the default size is pretty small, and I just wanted to post an idea on this as well. I tried this using firefox, edge and internet explorer.
@itay, can you maybe elaborate on how you managed to change the size of the geometry picker window? Is it just a matter of a different browser (e.g. Chrome or Opera), or is there some other kind of trick involved?