Another Tuvie episode I liked a lot is "Innocence". Not only did the epsiode deal with aging (something they were unwilling to explore with Kes' character but that's another topic) but I enjoyed the interaction between Tuvok and the "kids".
My favorite line:
Child: "Mr. Tuvok, what are your children like?"
Tuvok: "Well behaved."
I like 'Innocence' as well.
My fave Tuvok line is in 'Scientific Method'. Janeway is complaining about crewmembers not doing their jobs, and Tuvok responds with:
TUVOK: Shall I have them flogged as well?
Such a dry sense of humour.