たいして…ない => ~is not much of~ N3
Emphasis on degree
としている => be about to N2
Time
てもよろしい => You can… N4
Allow
はいいとしても => Even though... I accept it N2
Coercion
てしまっていた => Did by accident / finished N4
Completed
[際「さい」]して/に([際「さい」]し)/に[際「さい」]しての => At the time of A (which starts now).. N2
Time, Situation
てもよろしい => also possible, potential N4
Ability
てもよろしい => It's okay (Concession) N4
Concession
決して~ない => never; by no means ~ N3
てもよろしいでしょうか => May I... N4
Allow
(さ)せてほしい => Please let me do N3
Allow
ときとして…ない => At no time N2
Emphasize the negative meaning