The Alchemist 3:35 - 3:42 / The Aftermath 3:51 - 3:57 / The Edge of Darkness 4:47 - 4:53
Genghis Khan 1:46 - 2:10 / Hallowed Be Thy Name 1:18 - 1:36
The Fugitive 0:47 - 0:57 / Fear of the Dark - Verse Backing
Dance of Death - Second part of the intro - Verse backing / Face in the Sand - Intro (also sounds kinda similar to Blood Brothers)
Brighter Than a Thousand Suns - 2:33 - 3:17 - Lord of Light - 3:50 - 4:53
Losfer Words - Intro / The Duellists - Intro
Alexander the Great - 1:07 - 1:35 - The Loneliness of the Long Distance Runner - Intro
The Alchemist 3:35 - 3:42 / The Aftermath 3:51 - 3:57 / The Edge of Darkness 4:47 - 4:53
The melodies from The Aftermath and The Edge of Darkness start similarly, I'll agree on that. To me, it sounds like the latter is a more "developed" theme based on the former.
The one from The Alchemist doesn't strike me as very similar to either of them. Plus, Steve Harris is not the principal writer of any of the three songs. The two songs from The X Factor are Bayley/Gers/Harris collaborations, and The Alchemist is Dickinson/Gers/Harris.
Genghis Khan 1:46 - 2:10 / Hallowed Be Thy Name 1:18 - 1:36
No. If there is a riff in Hallowed Be Thy Name that is similar to that part in Genghis Khan, I'd rather mention the one at 4:05 in the studio version (although it is slower, the note pattern is more similar). I would still consider it a stretch to call them really similar, though.
The Fugitive 0:47 - 0:57 / Fear of the Dark - Verse Backing
Sorry, I don't buy this one either. The chord progression is different .Dsus2 - Csus2 - Am -Bbsus2 -Bbsus2- Csus2 - Dsus2 is how I play this part of The Fugitive on guitar. If playing it all using power chords only, it is D-C-A-Bb-BbC-D. FOTD on the other hand (first verse) has the following chords: D - Bb - C - Bb - C - D - Bb - C. Also, the rhythmic feel to the two is different. The only thing I feel they have in common is that they are in D minor.
Dance of Death - Second part of the intro - Verse backing / Face in the Sand - Intro (also sounds kinda similar to Blood Brothers)
This one I agree on. The intro to Face in the Sand quotes the part of Dance of Death at 0:20. I don't think there is much resemblance to Blood Brothers, though. And again: One Gers/Harris and one Smith/Dickinson/Harris.
Brighter Than a Thousand Suns - 2:33 - 3:17 - Lord of Light - 3:50 - 4:53
This one I have noticed myself. The only difference here is that each chord is repeated in Lord of Light. In BTATS the base note in the chord is E - C - A - F and then E-C-A-F again. In Light, the E chord arpeggio is played twice, then the C hord arpeggio twice and so on.
However, and now I am repeating myself: Both songs are Dickinson/Harris/Smith collaborations, not solely written by Harris.
Losfer Words - Intro / The Duellists - Intro
I have already explained why I don't find it meaningful to call these similar.
Alexander the Great - 1:07 - 1:35 - The Loneliness of the Long Distance Runner - Intro
I'll give you that the guitar melodies are partly similar (the first 7-8 notes in the riff are the same). However, the music as a whole does not sound similar at all (different rhythm guitar, different chords, different drumming).
To summarize:
- Some of those you list are really quite similar, to such an extent that they seem to be deliberate. But saying that it is characteristic of Steve Harris is simplifying too much. Many of your examples are collaborations between two or three band members, and in neither of those collaborations Harris has been credited as main writer.
- If those "quotes" are in fact deliberate, I do not think it takes anything away from the songs/albums. Classical composers have done it many times as well ; a theme or motif which is used early in a work, is repeated later with some variations. It serves to give the work a unified feel, and it rewards the listener when he recognizes a familiar melody.