"a couple of things" in a formal letter?

Is it inadequate to use "a couple of things" in a formal letter? If so, what word or phrase would work better?

Example:

I`m writing to inquire about a couple of things regarding my new job placement.

Solution 1:

'a couple of things' may not be appropriate in formal letters, especially because of the word 'things' which is used for everything without a specific meaning. I would recommend using 'a few/several/a couple of aspects/ issues', and if possible use a specific word that describes and substitutes 'things'.

Eg: We discussed a few demands, which are relevant for us.

Compare with: We discussed a couple of things which are relevant for us.

Register varies.