幸いなことに => fortunately; luckily; thankfully ~ N2
…ものとおもっていた => Thought it was... N2
Vague
のももっともだ => no wonder; …is only natural N2
~と言ってもせいぜい~だけだ => Even if it’s said that…but it’s just…. N1
Emphasize
[決「けっ」]して~ない => Won’t, isn’t N3
Will, Decision, Doing
... だけの ... => have enough to... N2
Emphasis on degree
~のは…ぐらいのものだ => only (emphasis) N1
Limit
その[結果「けっか」] => Because of A (in the past), B N3
Reason, Result, Response
けっか => as a result of; after ~ N3
Result
わけても => Especially N1
Emphasize
だけ(のことは)あって/だけのことはある => no wonder; as expected of; not ... for nothing; not ... with nothing to show for it N2
ものもV-ない => is not entirely impossible N4
Emphasize the negative meaning