They're two defining hip-hop albums and way more important than Illmatic.
I consider Astral Weeks to be more important.
I debated putting him at nuraber 1, Woody Guthrie is undeniably the most important folk artist ever, and folk is also undeniably one of the most important genres ever.
I'll leave the non-bolded ones up for debate than put them in appropriate slots if they make it.
The bolded ones i'll put in a to be added category, and i'll add it during my next revision I suppose, or just stick them in place whenever and not bother re-doing the whole thing.
To start the debate:
Nirvana im so-so about, I don't consider Nevermind to be anywhere near their best work even if its considered the 'most important'. I mean pretty much any Nirvana album could've came out at that point and featured Smells Like Teen Spirit and been just as successful.