描述
Converting a lossy file to another lossy format is a bad practice, the audio quality reduces 2 times (YouTube converts the upload on their side, and freyr converts it again), 3 times if the uploader sent a lossy audio too.
Sure, converting to AAC 320kbps is probably ok for YouTube's audio quality, but then you are creating bigger files for no reason. One of the songs I used to test it was 3.94 MB when downloaded, and 9.48 MB after conversion. Trying to reduce the bitrate to match the source size would be gambling with the audio quality too, since the same bitrate with different formats gives different results; a 128 kbps opus has higher quality than a 128 kbps aac.
Could you add an option to keep the original file, probably opus, and do everything else (tagging, organizing, etc...)?