Life After Death for me.
Life After Death was like Big's resume of why he's the greatest to ever do it, how he mastered his craft. He had every type of record a rapper could possibly make. He had your club records, storytelling records, your girl records, your wine & dine a chick record , your hard east coast street records, Diss tracks, he had a tribute record, stunting records, a fast rapping record where he did Bone thug's style better than them, dark records. This album was him doing it all and none of it sounded forced or out of place to me. It all felt natural for him to be that versatile.
For anyone who's younger they may take this for granted as everyone tries to give you albums that have a little bit of everything (and most fail miserably....see J Cole being forced to make records like Workout, had he come out in the 90s he wouldn't be forced to do such a thing and would have stuck to his lane) but back then I can't say it was like that.....
Take damn near any album from that period, Only Built for Cuban Linx, any Wu album, Reasonable Doubt, Beats Rhymes and Life, Ridin Dirty, Illadelph Half-life, The Coming, Muddy Waters, hell on earth, Stakes is High, Atliens, It Was Written, The Score, they simply didn't have the versatility of this album.....guys weren't making albums for EVERYONE, to me Life After Death did that, in some ways it fukked up the game.....It was like the modern day blueprint for making a rap album for a while. You had to be able to do everything after this album dropped or you weren't going to be very successful rapping.
Between that and Biggie being a better MC (he grew tremendously lyrically, flow wise,etc) , I think that puts it over RTD to me......It's tough but I think LAD is the better album.
I do find myself listening to Ready to Die more when I'm depressed, down, angry, hungry and LAD in any other mind state.