Being a responsible man, arriving half an hour late would surely surprise his wife. But then he thought that it'd be funnier if he waited a couple of hours.
Vs.
Being a responsible man, he would surely surprise his wife if he arrived half an hour late. But then he thought that it'd be funnier if he'd waited a couple of hours.
First, I would like to know if after the participial phrase "Being a responsible man", one should use the noun it modifies, he?
Moreover, the first sentence seems lacks a subject.
Second, whether "would" is necessary before "waited" or not or both are possible depending on the sentence.
Actually these sentences are two corrections by seemingly two English-speakers for a post by a non-native speaker.
Best Answer
Especially since the sentence uses informal contractions (it'd) it could say:
Whether to use past perfect depends on whether the man is looking forward to looking back upon the joke or is enjoying it now:
If would be funnier if he had waited...
It would be funnier if he waited...