Expressing "Both A .. and B" I came across the following sentence:

我既是一个语言的从教者，也是一个语言学习的爱好者。

I understand that "既 A , 也 B" is a sentence structure for expressing "both .. and ..". 

I was wondering about what effect 既 has on the meaning? Consider the same sentence above with 既 omitted:

我是一个语言的从教者，也是一个语言学习的爱好者。

Has the meaning or feeling of the sentence changed? Is either preferred in some contexts?
我是一个语言的从教者，也是一个语言学习的爱好者。


This sentence reminds us of the fact that I'm also a language hobbyist(assuming I'm well known as a 语言的从教者). 


  我既是一个语言的从教者，也是一个语言学习的爱好者。


With 既, it parallels the two roles (语言的从教者 and 语言学习的爱好者), which share the same level of importance.