[i'm not forcing you change the way to think and feel about the said character you like.]
[No, I'm not talking about the real life heroes like ones in the military, I mean the fictional ones ,even in the MLP universe.]
Heroes or anyone that holds supernatural or abnormal capabilities and abilities could pose a danger, cause to me it's a little unwise to let the said person have such power with no way to keep them in check. One example would be superman, the man of steel with much higher limits than anyone, at least from my perception.
Twilight is a nice, pure, and a strong leader like shown in the show, but what she is able to do gives me thoughts that says someone needs to keep her in check and same goes for the other princesses. Their government is similar to that of a monarchy at appears that way and that means giving virtually everything to one entity. It doesn't go down to reputation the way I see it, to me it's more of "It's a possibility" or a "just in case" kind of scenario.
You've all seen what you or what she is able to do, story wise at least. Wouldn't hurt to at least keep an eye on her like that. First impressions could fool anyone, like how sans was able to hide his true abilities unless needed and same goes for papyrus.
The prophets of the covenant work very similar as monarchs, so you can already see how it works, but in Halo 5 [spoiler Alert] Cortana is granted to a great amount of power from these new weapons made by the forerunners. It was said to be a "Imperial Peace" and from what is shown the UNSC see her as a threat now and what's a little funny to me is that Master Chief was the first to see it.
I guess it all comes down to, "there needs to be balance in all this"
If you have a fictional character on how they could be a threat then tell me.
It is your decision and your decision alone on how you think about this.