ad #1) yes, but remember that this only happens if the bean gets used on different views which use GET! This is not often the case. Usually you have 1 'entry page' with GET and then just do POST in between the other pages.
ad #2) yup true, will take a look tomorrow.
ad #3) do we have a default separator defined as static public final String somewhere already? I just did like to use a different one for the viewId than for the viewParameters.