~のぼる  => To increase N2
Reach level
~みこみがたつ => have a good prospect N1
Expected
を中心に => focused on; centered on~ N2
... おぼえはない => don't remember... N3
Position, perspective
いつか ... た => Formerly (At some point) N4
Time
~Vた + せつな => moment, instant, juncture N1
Beyond expectations
[中心「ちゅうしん」]に => With A as the center N2
Miscellaneous
~且つ(かつ) => and N1
Line up, list
つつ => while; even though; despite ~ N2
~としたことが => ~ surprised N1
Surprised
にこたえ(て) => in response to ~ N2
ひとつには…ためである => Partly because of ... N3
Cause, reason