Well
John and
Jonathan are two separate names that just happen to sound similar. I prefer
Jonathan's long sound over
John's simple plain sound most of the time.
For
Jonathan I prefer nicknames like
Jonny or Nonny (a friend calls her brother
Jonathan this) and rather dislike
Jon but
Jack is alright.
Jack isn't really correct seeing it comes from
John which is a different name.
For
John I think that
Johnny or
Jack are perfect nns and nine times out of ten I prefer
Jack as a full name on it's own.
Jack Nathaniel is a favorite combo of mine that actually has both of the
John and
Jonathan elements (and meanings) to it.
I really do prefer forms of
John over
John itself. Scottish forms like
Ian /
Iain are delightful as are
Ioan,
Sean,
Evan,
Owen,
Eoin,
Hans,
Yoan and
Yannick.