Your initial instincts were better. It's about time she came home.
It is a subjunctive. But better would be
Yes, she should be home by now.
When your wife or daughter finally arrives, very late, then you would say:
It's about time she came home!
EDIT: You would exclaim the above only after wife|daughter had finally gotten home because it means The person has done what was expected of him or her (in this case, gotten home) but has taken a very long time to do it. Another example: diner at a restaurant waiting a very long time for the waiter to come over to his table. Waiter finally arrives. Diner says curtly:
It's about time you came over! or It's about time you waited on me!
The Sun-Times example We did the documentary about four years ago. It's about time to go back and do a follow-up. has an infinitive "to go" after "it's about time" whereas your sentence has a past-tense "came" (acting in a subjunctive role). The Sun-Times scenario is not an analogue for your situation.
The follow-up is due. Your wife|daughter is overdue.
If the documentary producer wanted to convey the idea that the follow up ought really to have been done long before now, that too much time has elapsed, he would say:
It's about time we went back and did a follow-up.
EDIT 2:
And to confuse things even further, intonation pattern can change the meaning.
It's about time she came home!
means she has not yet arrived and is long overdue.
It's about time she came home!
means she has finally arrived home.
If you are blaming the person, with whom you're talking, then ustanak is correct...
Unlike you, I don't waste my time.
However, this means that the person with whom you are talking does waste time.
If you want to say a general statement that is less insulting, you can use the following...
I don't like to waste my time, unlike some people.
You still have to be careful when saying this phrase because, if you emphasize the word some, it can still sound insulting to the other person.
It's always more polite to talk about yourself and not speak negatively about others. If it were me, I would simply say...
I don't like to waste time.
Best Answer
"It's about time" is very commonly used to indicate something is past due:
It's mildly sarcastic, because the other meaning is that it's the proper time:
If I say to my family, "Finish up whatever you're doing; it's about time for dinner," there's no sarcasm implied. If my family says to me, "When are we eating? Isn't it about (or around) dinnertime?" That isn't sarcastic.
If my family says to me, "It's about time you serve (or served) us dinner!", that is sarcastic, and I might invite them to try cooking their next meal themselves.
Note that "it's about time" is often followed by the past tense: