No, it isn't quite right. People are who and whom. Things are which.

"Ramekin". in the sense of a small, typically ceramic, bowl or container used for serving various foods, is not a common word. A chef or a gourmet or "foodie" would know it, but not your average diner. Crème brûlée, for example, is usually served in a ramekin, but most people would say it comes in a small bowl or dish, and leave it at that. You don't have to replace "ramekin" with some other word, but you might want to consider the possibility of doing so, or at least explain what the word means by, e.g., writing "These ramekins, or small dishes, are designed to resist high temperatures..."

Even if it has something to do with rarity I don't see why we have to reject this:

https://www.ldoceonline.com/dictionary/few

Few means ‘not many or hardly any’. It emphasizes how small the number is.

By the way, can you provide a link to a dictionary where it is said anything about FEW linking with RARITY?

Hi teachers,
Is it normal nowadays for a 23 years old boy to call his aunt "Mrs. Jones"? I mean to use "Mrs."? She's is single as well.

Thanks.

Hi,

Are the following sentences okay?

a. Peter is one of 15 astronauts to have landed on Mars.

b. Peter is an astronaut to have landed on Mars.

c. Peter is one astronaut to have landed on Mars.

Which word would you use instead?

Can occupation apply to a temporary on-going activity?

- What are you doing now?
- I am making a craft.
- Good occupation.

“Come read with me,” Susan said to Anne.

This is an example where the comma would be placed inside of the quotation marks.

Should it be "inside the quotation marks" instead?

Thanks!

An uncountable noun is singular

More information is available.

Therefore the pronoun is 'it' as a subject and object.
It is available.
I can send it.