A dub translation IMO is to transfer the script as acuratly as possible from the original with most of the intent in tact. Just fudging with stuff to make it how you want it seems lame to me
Wrong. That would be the job of subtitles. People watch subtitles because they want try to get as close to the original experience as possible (or dubs aren't an option), and so subtitles try to be as faithful as possible, within some reason (things that do not translated to English well generally define the amount of "localization", but in the end, a little isn't avoidable). The reason being that you want to understand it.
Dubs are different. Heck, most of those who want to watch something faithful would just stick with the subs, regardless of how good the dub could be.
But anyway, for dubs, the Japanese companies give the audio/video, and sometimes the scripts, and you can do whatever. It would be similar to giving someone the music and instruments of a piece. There is no obligation to follow the original to the letter. Sometimes adaptations are better than the original. It's kind of like doing an adaptation of a Shakespearean play into a movie, except the visuals are already done.
Sometimes doing changes results in something better, sometimes not. Sometimes changes are necessary due to laws and guidelines, and sometimes they are due to artistic flair.
You can take Robotech as an extreme example, since some of the reason for the way it exists is due to broadcasting requirements. Some people say it's better than the originals that were used to make it (I haven't seen Southern Cross or Mospaeda, only Macross. Actually, I haven't seen Robotech either). It's amusing how they are praised for doing it well, and people rag on them for changing from the original when they don't do it well.
In the end, if the script is different and you hate it because it's bad, then it's one thing. But if you hate the script because it's different from what you expected, then that's a different story. It's also similar to how people complain about an Anime being inferior to its Manga because it doesn't follow the original, which is probably true. But that doesn't mean the Anime isn't good still.
I think you're better off finding a good dub of a good anime (and not caring if the script was significantly changed from the original) and letting your friend know that the subtitled version might be different and could be considered better. That might get your friend to try subtitles and then maybe you won't have this problem anymore.
As for OP/ED, getting licenses to include the OPs/EDs/inserts is a different story and can drive up the costs, so they won't always go that far just to get a song or two, so I wouldn't be surprised.
