I have often come across the expression "crowded with a lot of people."
Isn't it enough to say "The hall was crowded"? Why should we add "with a lot of people" to it?
Another:
He lost his composure and equanimity.
In view of the fact that composure and equanimity mean almost the same thing, isn't it quite pointless to use them together at the same time?
Just to be clear, Niall's 'this' refers to the tendency to repeat, not to the word "equanimity" - which I (born and raised in the home counties) have heard (and used) quite frequently.
Incidentally, I'd hesitate to call it nearly synonymous with composure anyway. Composure is a temporary thing, that can be learnt; equanimity is more of a character trait.
b
"The hall was crowded with a lot of people." is redundant, but 'The hall was crowded with people.' is not redundant. [crowded with people as opposed to crowded with (people and) other things]
I don't agree that "crowded with" (necessarily) means overcrowded.