long suit vs assemblage

long suit and assemblage both are nouns.

Word	Noun	Adjective	Verb	Adverb
long suit	Yes	No	No	No
assemblage	Yes	No	No	No

As nouns, assemblage is a hypernym of long suit; that is, assemblage is a word with a broader meaning than long suit:

Other hypernyms of long suit include accumulation, aggregation, collection.

long suit (noun)	assemblage (noun)
an asset of special worth or utility	the social act of assembling
in a hand, the suit having the most cards	a system of components assembled together for a particular purpose
	a group of persons together in one place
	several things grouped together or considered as a whole