See, to me, Fear of the Dark is definitely the weakest Maiden album. It's not even close. It has about five songs I would ever even consider going out of my way to listen to (title track, Afraid to Shoot Strangers, Wasting Love, Judas Be My Guide, maybe Be Quick or Be Dead), and the rest is quite mediocre. Chains of Misery, The Apparition and Weekend Warrior are clearly Maiden's three worst songs. The album has some pretty strong standouts, but as an actual album-length listening experience, it's just not very good.
No Prayer for the Dying isn't great, and is probably my second-least-favorite Maiden album, but it's miles ahead of Fear. The first two songs are duds, but the title song through Run Silent Run Deep is actually a pretty good run. Hooks In You and Bring Your Daughter... to the Slaughter are pretty weird and mediocre, but the album finishes strong with Mother Russia. Fear's best songs are the best songs from either album, but it is not that good of a listening experience as an album start-to-finish, while No Prayer is pretty decent in that regard.