Gosh, that original vs. English dub clip ... It's like night and day. The Tuxedo Mask/Mamoru reveal to Sailor Moon in the Japanese version is really cute and well-handled. Tuxedo Mask graciously thanks Sailor Moon for protecting him, and that it's his turn to protect her. In the dub, Sailor Moon acts really disappointed that Mamoru is Tuxedo Mask, and Tuxedo Mask acts like a jerk to her, saying that the fight doesn't concern her.
The dub did so many unnecessary changes in the dialogue. So much so, in fact, that I think they made many of the main characters very unlikable the more I think about it. The Moon and Mars rivalry you mentioned, doink, made both of them extremely unlikable, especially Mars ...
I remember when I was a kid watching the English dub for the first time, Mars was easily my least favorite character. I remember during one episode, the dub changed the dialogue so much to the point where it implied that Mars had taken the Crescent Moon Wand/Silver Crystal from Sailor Moon, and that she was willing to let Sailor Moon die in a battle without it. In the Japanese version Moon trusted Mars the most, and it turned out that she GAVE Mars the wand to protect because she didn't trust herself to keep it from the bad guys in attempt to save Mamoru. Why even change that at all? Of course I didn't notice this kind of stuff as a kid, but watching the original Japanese version just opened my eyes, and I haven't been able to watch the dub in a favorable light again.
As I said in another post in this thread, by the time S and SuperS was airing on Cartoon Network back in Summer 2000 (was that really 14 years ago? Wowza.), I had already started watching the Japanese version, so watching the new dub episodes on CN even at that point was a really tough experience, haha.
Jupiter has always been my #1 favorite Senshi, and when I saw how the dub handled her character during the Sailor Moon S episode when her pure heart was taken, I remember being so mad. When the monster was attacking her, she was saying "PLEASE, SOMEBODY HELP ME! Help me, please, anybody!" in the English dub and held a grudge towards Uranus and Neptune for not saving
her. In the original, she was simply crying out in pain, and she became angry later on because she assumed that Uranus and Neptune let Haruka and Michiru get hurt. That's a big difference! Jupiter comes across as much more selfless in the original, rather than helpless.