Oh, now I see what you mean!
This is not an instance where you are purposefully leaving words out, as occurs in memos and emails, or when we are writing a quick note to someone. The words like 'bit' and 'range' are 'understood' as being there. It is not so much whether a phrase such as 'a little tenderness' (=concern, sympathy) would be acceptable grammatically in a formal style, as whether expressions such as that sound too casual, flippant, for formal writing.
So, "you might at least have shown a little compassion when you broke the bad news to her" would be too casual, but formally you might say,
"A certain tenderness of voice and manner is an essential quality for the prospective Grief Counsellor."