にこたえ(て) => in response to ~ N2
ことこのうえない => the most of all; the best; nothing is ... N2
Emphasis on degree
に[答「こた」]えて => In response to A N2
Reason, Result, Response
といえば…ぐらいのことだ => speaking of... just... N2
Respectful, humble
~にたえる (耐える)    => bear doing ~ N1
さえ/にさえ/でさえ => Even N3
Not only, Not even
さえ/でさえ => even; so much as; not even N3
とみえて/とみえる => It seems that ~ N1
あえて => dare to N2
Suggestion
ここ/そこ/あそこ/こちら/そちら/あちら => here / there / over there N5
Spatial relations
の[末「すえ」]/た[末「すえ」] => conclusion N2
Reason, Result, Response
からこそ/~ばこそ/こそ => precisely because ~ N2