Would titanium be a better option for aircraft skin if cost were not a factor?
even assuming price would not be an issue, formability certainly would be. Ti is much harder to bend, drill and cut than Al so building a plane out of cheap Ti would significantly increase its manufacturing costs over Al. Ti retains its strength at high temperatures far better than Al but in subsonic aircraft like passenger planes, airframe heating is not a design limiter that would drive a choice between selecting Ti or Al.