Does 反面 require contrasting clauses?


I encountered the following example sentence in a book describing the uses of
反面:

> 仕事を辞めて自由な時間が増えた反面、緊張感もなくなってしまった。
>
> Since I quit my job, I do have more free time but I also lost my nervous
> feeling. (I'm aware this might be too figurative)

That translation sounds unusual to me because I do not think "not having a
nervous feeling" and "having more free time" contrast each other enough to be
joined with "but". I think they should be joined with "and". However, all the
sources I found state that 反面 is used to present different sides.

My questions are:

  1. Does the Japanese sentence, by virtue of using 反面 (and probably しまった), imply that the speaker believes "緊張感もない" is a negative consequence?

  2. Is 緊張感 considered a positive emotion in Japan?

  3. Would the sentence make sense if the clauses were combined with だけでなく or just the て形?

EDIT: My reasoning behind question 3 is that, based on the translations of 緊張感
[(Jisho.com reference)](http://jisho.org/search/%E7%B7%8A%E5%BC%B5%E6%84%9F),
"仕事を辞めて自由な時間が増えた **だけでなく** 、緊張感もなくなってしまった" would mean "...not only do I have
more free time, I also lost my feelings of nervousness." Is this not a natural
way of using だけでなく?




>   1. Does the Japanese sentence, by virtue of using 反面 (and probably しまった),
> imply that the speaker believes "緊張感もない" is a negative consequence?
>

Yes.

>   2. Is 緊張感 considered a positive emotion in Japan?
>

Not always. It depends on the context.  
緊張 usually has a negative connotation, but 緊張 **感** is often used in a
positive meaning. And here in your context, it is used as a positive emotion.

>   3. Would the sentence make sense if the clauses were combined with だけでなく
> or just the て形?
>

「仕事を辞めて自由な時間が増えた **だけでなく** 、緊張感もなくなってしまった」 doesn't really make sense.
「仕事を辞めて自由な時間が増え **て** 、緊張感もなくなってしまった」 doesn't sound too good, either. I would
rephrase it as:

> 仕事を辞めて自由な時間が増えた｛が/けれど/けれども｝、（逆に/反対に）緊張感はなくなってしまった。(も→は)  
>  仕事を辞めて自由な時間が増えた｛が/けれど/けれども｝、（同時に）緊張感もなくなってしまった。




>   1. Does the Japanese sentence, by virtue of using 反面 (and probably しまった),
> imply that the speaker believes "緊張感もない" is a negative consequence?
>

Yes.

>   2. Is 緊張感 considered a positive emotion in Japan?
>

Not always. It depends on the context.  
緊張 usually has a negative connotation, but 緊張 **感** is often used in a
positive meaning. And here in your context, it is used as a positive emotion.

>   3. Would the sentence make sense if the clauses were combined with だけでなく
> or just the て形?
>

「仕事を辞めて自由な時間が増えた **だけでなく** 、緊張感もなくなってしまった」 doesn't really make sense.
「仕事を辞めて自由な時間が増え **て** 、緊張感もなくなってしまった」 doesn't sound too good, either. I would
rephrase it as:

> 仕事を辞めて自由な時間が増えた｛が/けれど/けれども｝、（逆に/反対に）緊張感はなくなってしまった。(も→は)  
>  仕事を辞めて自由な時間が増えた｛が/けれど/けれども｝、（同時に）緊張感もなくなってしまった。

