Before we get much farther, I'd like to address the elephant in the room. I don't think of any Monty Python sketches as being FARCES. Most of the time nowadays we think of farce as being slapstick, which MP certainly did little of. But even in the classic sense of a light comedy centered around situations rather than around character development, this definition falls short. MP utilized absurdity and surrealism far more than situational humor. Fawlty Towers is much closer to a farce in that sense.
All right, I'll get off my pedestal, because I liked the puzzle overall. Once again on a Monday, I don't have much time to consider what the theme might be, but I had an insight as I worked my way down and had the following at 48A: ____TYKE_____. Just luck, but I knew there had to be a reason that was there.
The revealer is great: 58A: Part of a person's psyche ... or a hidden part of 18-, 23-, 39- or 48-Across? (INNERCHILD). This is exactly right. The four hidden children are a minor, a teen, an infant, and the aforementioned tyke. You could quibble that a teen is not exactly a child, but then you maybe don't have teens in your house. They're still children, believe me.
The four theme answers range from great (QWERTYKEYBOARDS, although that plural..., and CAPTAINFANTASTIC, which I highly recommend as an interesting if very odd movie) to the less interesting (PRIVATEENTRANCE and CAMINOREAL). But they're all solid, so the theme works well.
There's some strong fill here as well: SEXTANT is very nice (when I had SEX____, I thought it was going to be "sex tape". There's my mind, in the gutter again). I like me a good Star Trek reference, so STARSHIP was welcome. I myself like a raisin dessert from time to time, although I basically never buy a RAISINET.
There's another re- answer here, but RESENDS is at least reasonable.
1A: Fruit often seen in still lifes (PEAR) - C+.
Fave: AHME (54A: Sigher's words) - those words in the opening song of my favorite G&S, Yeomen.
Least fave: 26D: "High" times (NOONS). No. I don't understand a plural of a specific time.