Hasn't it also occurred to you that if the English patch version was able to replace Japanese text with fan-translated English text, then you will be able to replace the fan-translated English text with the professionally translated English text, with the same method no less? On the other hand, you can also just replace the Japanese voice files with the English counterpart, like you said. But I wouldn't recommend it. All I need was one look at the iso and its compressed data files to know that it would be a whole lot of unnecessary problems.
But you're not just asking how to do it yourself, right? You're asking if anyone else is "planning" to do it. In which case, I think you should wait a month. If you don't see anyone putting one up, then I guess you should stop waiting and do it yourself.