[MASSIVE SPOILER ALERT!] Observations from the S5 finale

Here's some thoughts of the tip of my head:

- Starlight Glimmer is an idiot. Instead of using her time spell to make sure her "friend" didn't get his cutie mark, she goes for unnecessary and overblown vengeance.
Consideration:
Magical communism born from jealousy and fear?
Where have we heard something similar before, hmm?

- Twilight Sparkle and her friends are essential to the existence of Equestria.
Consideration:
No matter what outcome, at least ONE of the threats loomed over Equestria.
But what alternatives were used to defeat the others?
Why was Celestia so weak and powerless?

- The villains CAN be defeated in other ways than Twilight and her friends, as evidence of the different outcomes of the future.
Consideration:
The first time, when the Rainboom failed, it was Sombra. What happened to the other villains in that timeline?
Also, if the spell always brought them back to the same time in the future, WHY have some villains never appeared?
Was the final trip the effect of ALL villains being able to win?

- How come Starlight Glimmer never saw the oucomes? Where was she every time Twilight used the spell, for her to be "pulled along"?
Consideration:
The spell can't be used without the map.
Did that mean that Starlight was stuck in the past?
And how did she always manage to activate it on Twilight in the past?

- The time spell is ridiculously overpowered. It can go ANYWERE and ANYTIME in Equestria. Why didn't Twilight go to a TOTALLY different time, hence pulling Starlight with her?
Consideration:
There might have been other "failsafes" built into the spell.
Why didn't Twilight use it to travel to Starswirl's time, freeze Starlight and learn how the spell SHOULD work to stop her completely?

- Why didn't Twilight do a single thing in any of the futures?
Consideration:
It's not like it could have changed anything more than the past had changed already.
And it could have been a good way to learn.
Answer:
Time limit of the episodes.

- Why didn't Luna... Excuse me, Nightmare Moon be surprised by the existence of ANOTHER alicorn.
Consideration:
Where was Cadance in all of the futures?