を中心に => focused on; centered on~ N2
[中心「ちゅうしん」]に => With A as the center N2
Miscellaneous
中 => While (Lasting) N3
Continuous
途中で/途中に => on the way; in the middle of ~ N4
中 => During the period (Term) N3
Time
最中に => while; during; in the middle of ~ N3
途中 (は) => on the way; in the middle of ~ N3
Halfway
中 => Throughout, all over, during the course of N5
Time
(の中)で~が一番~です => out of this group, [A] is best N5
[最中「さいちゅう」] => In the middle of A N3
Time, Situation