まさか...とはおもわなかった => never thought that N3
Surprised
はさておき => setting aside ~ N2
Trend
お…くださる => Please do ~ (honorific) N3
Respectful, humble
まさに => exactly, surely, certainly N2
Confirm
させておく => Leave it alone, don't interfere N2
Position, perspective
お~願います => please do (A) N2
させてください/させてもらえますか/させてもらえませんか => please let me do N3
~とおもうまもなく => Suddenly~ N1
Right after...
いまさらながら => Still ... now N3
Time
おまけに => A. In addition, B N2
(Not)only, (Not) even
いまさらのように => Now... again... N2
Time
はさておき => A aside; putting A aside, B (new topic) N1
Miscellaneous