XばかりでなくY(も)
Usage
This structure is similar to XだけでなくY(も) and means "not only X but also Y".
Examples
あのレストランは、安いばかりでなく、とても美味しい。
That restaurant is not only inexpensive but also very delicious.
一生懸命勉強したら、日本語が上手いになったばかりでなく、成績も良くなった。
By studying hard, I not only became proficient in Japanese, but my grades also improved.