How about shorter... but kind of tousled?  the Meg ryan style we all loved is still flattering and youthful.   Leave the straight hair to the young women.  I think the bob is very aging (especially when women insist on dying their hair a dark color)... but so many women in their fifties and sixties like the look but I think it pulls a face down and ages a woman to have straight hair around her face after age 40.