Sentence translation help (「そう長く生きていない」「まだここに来て日の浅い」)


I was having trouble translating this sentence, specifically the last part:

> だが、 **そう** 長く生きていないとはいえ、人生の半分以上をここで暮らし、また言葉を操る『言ノ葉使い』である僕には彼が
> **まだここに来て日の浅い** 使用人であることが分かった。

I understand that 「長く生きていないとはいえ」 means something along the lines of 'although
I haven't lived that long', however I'm not sure about the function of 'そう' in
that sentence. I translated the next part as 'living here for over half my
life', and the next one is about him being able to use 'Kotonoha' to
manipulate words. However the last part confuses me a bit, specifically the
use of 'まだ', and also the use of te-form in '来て日'.

Also '浅い' usually translates to 'shallow', but can it be translated to 'young'
in this context?




  * そう corresponds to _that_ in "that long". It's interchangeable with そんなに and それほど. 

> そう簡単ではない。 = そんなに簡単ではない。  
>  It's not that easy.

  * `(te-form) + 日が + 浅い` [is a set phrase](http://jisho.org/word/%E6%97%A5%E3%81%8C%E6%B5%85%E3%81%84) meaning "it hasn't been long (since ～)". の is replacing が because this part is in a relative clause. まだ is simply _still_ or _yet_ , and is often used with this set phrase.

> 彼はここに来て日が浅い。  
>  It hasn't been long since he came here.

The sentence is about the time after he came, not about his age.




  * そう corresponds to _that_ in "that long". It's interchangeable with そんなに and それほど. 

> そう簡単ではない。 = そんなに簡単ではない。  
>  It's not that easy.

  * `(te-form) + 日が + 浅い` [is a set phrase](http://jisho.org/word/%E6%97%A5%E3%81%8C%E6%B5%85%E3%81%84) meaning "it hasn't been long (since ～)". の is replacing が because this part is in a relative clause. まだ is simply _still_ or _yet_ , and is often used with this set phrase.

> 彼はここに来て日が浅い。  
>  It hasn't been long since he came here.

The sentence is about the time after he came, not about his age.

