Man that's tough. Especially the 90's onwards.Four favourite albums of mine, all debuts from different decades .
60's King Crimson - In The Court of The Crimson King
70's Roxy Music - Roxy Music
80's The Stone Roses - The Stone Roses
90's Pearl Jam - Ten
I'm skipping the 60's because I don't like it.
I'm not much of a 70's guy either but
70's - Kiss - Self Titled.
80's - The Smiths - The Queen is Dead
90's - Counting Crows - August and Everything After
00's - AFI - The Art of Drowning
10's - Marmozets - The Weird and Wonderful Marmozets or The Gaslight Anthem - Handwritten
20's - Turnstile - Glow On or Spanish Love Songs - Brave Faces Everyone
I could pick about 20 for each of the 90's, 00's and 10's.