Why does everyone just assume the english version is going to be bad? lol I have faith that the localization team will do a great job despite the songs and idol stuff.
The compositions were written for Japanese text for lyrics. Fitting English into a Japanese song is always possible, but sometimes the results are a little awkward because of how the translation and localization works.
That, and there hasn't been too great a track record (or many examples) of really outstanding Japanese to English video game music localizations and performances. And with the whole VA union business going on right now, coupled with how the performers have to be chosen with that in mind, they'll need to be talented both in VA work and vocal song, not to mention it's already a pretty small pool of people... well, the results aren't really favorably skewed for it. It doesn't seem like the music was made with considerations to have it sung in more than one language to alleviate these fears.
This is just a small reason why localization is one hard-ass job.