This means that scales, arpeggios, and chords can help you grow as an organist as well because
a) they will help you develop your music theory skills,
b) they will help you develop finger dexterity and independence,
c) they will facilitate the learning process of real organ compositions.
If you would like to practice organ scales, arpeggios, and chords, here is what I suggest you do:
Take a pair of two keys with the same number of accidentals (C major and A minor) and spend with them 1 week.
Then the next week practice scales with 1 sharp (G major and E minor).
Then the next week - with 1 flat (F major and D minor),
2 sharps (D major and B minor),
2 flats (B flat major and G minor),
3 sharps (A major and F sharp minor),
3 flats (E flat major and C minor),
4 sharps (E major and C sharp minor),
4 flats (A flat major and F minor),
5 sharps (B major and G sharp minor) or 7 flats (C flat major and A flat minor),
5 flats (D flat major and B flat minor) or 7 sharps (C sharp major and A sharp minor),
6 sharps (F sharp major and D sharp minor) or 6 flats (G flat major and E flat minor).
Some people feel they need to review the fingering of the other scales on the same week. I wouldn't worry about them because:
a) the fingering of one scale often reinforces many other scales
b) you will go back to the beginning after these 12 weeks. That would be a time for review.
By the way, do you want to learn my special powerful techniques which help me to master any piece of organ music up to 10 times faster? If so, download my video Organ Practice Guide.