there are varying degrees of influence
to me, when it comes to nyc hip hop.. the most important influential groups of the 90s were wu, big/puff, nas/mobb deep, jay-z. an entire industry was built aroundthese guys and would spawn COUNTLESS imitators while they all took pieces from each other pretty much.
for example nas illmatic wasnt really influential on anyones sound, which was really borrowing the sounds of tribe, gangstarr, etc but the lyrics were influential to other emcees in the ny area which cant be underestimated
im pretty sure that the entire nyc mid 90s crew (wu, bad boy, nas, mobb,jay,etc) all bit off each other here and there,
cuban linx didnt set the industry on fire but it influenced every artist in the immediate genre. rza was a trendsetter in the same sphere as puff and had to compete with his sound. the resulting marriage made all i need THE rnb/rap prototype.
tho i would same CREAM itself is prolly the most influential song IN hip hop as the idea of getting money in hip hop has now become 1 in thesame.
no way out was an influential album that jay and nas and even wu would use pieces from to fit into the changing commercial landscape (from city is mine to chez chez laghost)
blueprint set the soul sample wave but was influenced directly from supreme clientele. nas said it best on last real nikka alive about how jay was trying fit on with them.
mobb deep to me were THE premier street hip hop group , and set the standard for guys like the lox, dmx, beanie, state props, cnn, etc sounds and they leaned on wu and nas a lot too
and from those 5 acts, entire movements, and even genres were built.
the entire underground rap industry basically come from these guys and even today the trends they set have become common place in hip hop as almost rules of the genre.