Marriage is the name of mutual understanding. its not by obedience husband and wife work with each other. If it is Allah's obedience both seek in act and spirit, they support one another in goodness and help each other stay away from evil. It is however, in some cases wife has to take husband's permission before carrying out certain acts (of course for those seeking Allah's pleasure above personal egos). This icludes her leaving home.
well my personal opinion
I think if a person marrys someone
there own age
there better off to understand each other better
to have more energy, have fun together, have many similarites...which make life a bit more exciting.
Age difference anywhere from...4-5years and higher
(personal opinion)
I know Islamically age doesnt matter as long as both people are mature.