You seem to miss some important part of this why I think Forgiveness and Redemption fit her so well(which I didn't explein before so I do it now).

I didn't say it just because of her redemption and getting forgiveness for evil she did. Of curse it also is important part, but not only one.

She has great redemption but she not only become herself better person(which she try to do very hard, despite not so understandable and empathic enviroment) but also helped Twilight(human) to find the right way, when she(human Twilight) become demon like she before she help her to go back to normal and offered friendship, like Twilight(pony) do before for her.

And she not only get forgiveness but she also herself was very forgiving. She always forgive when others - also her friends - remind her about her past, she doesn't get angry at them or anything when they all the time put her aside(like for example: they set up Rainbooms, but didn't include her(despite she has music talent like she shows), and when Twilight come through the portal they immediately include her into Rainbooms), she always forgive. She also forgive Sci-Twi(even if at the beginning she become a little bit mad at her).

Those things aren't focusing on how she did something evil in the past but exactly on positive aspechts of her character.

Even in case of just her redemption and getting forgiveness it wouldn't be focusing of her bad past but actually of the positive side. Redemption is something very, very positive.

Redemption and forgiveness - not only as something she gets, but also as something she gives - was actually most important thing in her life, nothing influence her more.

And fogiveness is something very importang in friendship, and redemption generally.



Of course she was empathic too, but as i said it's not so plainly and importangt part of her like redemption and forgiveness.

And empathy isn't such good for element - already some way included in kindness(You know for example this scene in Friendship Games between FLuttershy and Sci-Twi, just before FLuttershy's power was drained out... wasn't this empathy too?)... and we could even say that would be also in forgiveness.



And her power... well I don't think is good idea to assign such big importance to it. Ok Twilight's element is magic(but in meaning: friendship or magic of friendship), and power of Sci-Twi is something what could be recognized as most typical equestrian magic - telekinesis, power of all unicorns - but what with the rest? Is super-strenght connected with honesty? Or super-speed with Loyalty?

Ok others are more moot - talking with animalst could be in some way connected with kondness(as kindness for animals), exploding confetti with laughter(as a something connected with parties) and creating diamond shields with generosity(as it was said she could also created some other things from this diamond and probably give it to someone)... but this all are still rather very weak connections. In such way this power still could be connected to forgiveness and redemption - as something what will help to better understand other in order to help them do their own redemption and get forgiveness.



Of course existence of seven gems itself really suggest that she really is Seventh Element of Harmony, but I think something what she get just now isn't such strong hint in topic what this Element would be. Taking her life as a whole suggest much more to Forgiveness and Redemption.