What was the best period of your life so far?

[Rusletov]

Мне кажется, здесь вообще следует скказать "What was is the best period of your life so far?"

The simple present doesn’t really work with so far.
Источник: https://forum.wordreference.com/threads ... t-20632791

On the other hand, I know that it's fine to say "This is all we know so far"

[Easy-Breezy English]

On the other hand, I know that it's fine to say "This is all we know so far"

It works in this case because here so far means at this point, and not until now. This slightly different meaning calls for a different tense.

[Andrea]

It works in this case because here so far means at this point, and not until now. This slightly different meaning calls for a different tense.

Absolutely.
In the same worderefrence thread, the very same user claims "What is the best event you’ve [ever] been to?" to be correct.

Hence, what is wrong about "What is the best period of life.../ the best time.../the worst experience..." and the like?

[Easy-Breezy English]

When you were a kid, what did you want to be when you grow up? (grew-up?)

Not critical at all. BTW, you don't need a hyphen with grew up.

What is your go to movie theater snack? (to-go?)

Go-to is something you use by default. For example, when I eat out, my go-to dessert is cheesecake.

What has been the best team building event you have been to? (team-building?)

Hyphenating compound adjectives is a recommendation, not a rule, and mostly a matter of style.

[Yety]

What is something you can never seem to finish?

https://idioms.thefreedictionary.com/can%27t+seem+to

What's on your bucket list this year?
When people come to you for help, what do they usually want help with?

I can't seem to figure out what's up with 'em sample sentences...=))

What's an unpopular opinion you have?
What's one place you've travelled (?) that you never want to go back to?

What are three things in your diet and/or training that went particularly well in the last phase? Why?
What's one thing you could have done better? Why? What's one thing you can do to make your next phase even better than the last?

1. What's one of the rewards of being a teacher ?
2. What's one of the most difficult things about being a paramedic ?
3. What's one of the best things about being a police officer ?
4. What's one of the most interesting aspects of working ...

What are you a natural at?

Friend: You mean, what's the most important thing to be a natural at? How about love?
Director: Ah, love. What does it mean to be a natural at love?

I feel it in my bones.” He gave her nose a playful tap. “Could be arthritis, you know, ever think of that? Oh sure, I guess I'm a 'natural' at some things—a natural clown, a natural athlete, a natural at losing at chess. But marriage?

Cf.:
He is a professional at what he is doing. He is so deceitful at it until, as stated before, he has untold millions of people caught in his snare. He is the great imitator of the Living God. He is so good at imitating the Lord Jesus ...
Antonio Conte directed more thinly-veiled criticism at Chelsea, claiming that he is a "disaster" at convincing the clubs to buy the players ...
He is a disaster at drawing, and as he struggles to correct his map, a cat suddenly drops down from a string tied to the ceiling.

What fictional place would you most like to go to?

Encourage learners to make up their own questions using the same formula (Which character would you most like to ...?) for others to answer. Example. Which character would you most like to go for a coffee with?

What would you best like to do if you were a sailor ? What would you best like to do if you were a farmer ? Would you rather be a sailor in summer or winter ? Why ? Would you rather be a farmer in summer or winter ? Why ?

[Andrea]

is a "disaster" at

[mention]Yety[/mention] ,
Cool examples! I've also found this one:
The series is about a henpecked jungle man who is a flop at cooking health food.

[Andrea]

Hyphenating compound adjectives is a recommendation, not a rule, and mostly a matter of style.

Thanks a billion! I've been racking my brain over getting my students memorise that:))