>>/12168/
> I know this episode is used to give context to potential trollestia/tyrantestia in canon, and while it is certainly meme fuel I partly disagree. While Celestia showed a joking side here."Gotcha!" and her little tea prank while Mr and Mrs Cake were fussing over her. I think the dynamic of this episode is that Princess Celestia is actually pretty laid back and everyone takes her roll as the immortal monarch of the realm a bit too seriously. I do agree it is a bit weird she didn't immediately explain Philomena but I don't think it crosses over into troll territory. She was soon interrupted by Mayor Mare's request with a personal audience after all. 
Absolutely. And from how the Summer Sun Celebration is treated both in the pilot and Cutie Mark Chronicles, I feel as though the pageantry of Celestia's rulership is almost more for the pony's sake than for Celestia's. Perhaps part of that is education and the culture of the past 1000 years, but I still get at least the impression that Celestia's political and social power stems primarily from the extremely high regard that almost all ponies hold her in. 
> The fandom started to play into that, and in some cases, really ask, why would Twilight be so afraid of banishment? I think here it is more of the innocence of this setting here and Twilight's obsessive personality over any basis for anything rational in universe.
Twilight herself admits she doesn't think that would happen - if she of all people had reason to think it really could happen she could just cite her reasons why, I'm sure she has a fairly good understanding of the Equestrian legal system, especially since she's still technically a kind of public servant. 
 >>/12169/
> Correct me if I am wrong, but, I think this was Philomena's only appearance in the show. 
I certainly don't remember her appearing again - but even background appearances could count. Another thing to keep eyes open for going forward. 
> Agreed. Presumably they do exist.
There will be precedent for imprisonment with Discord - a bold statement I could make so far for this first season is that we don't actually KNOW that imprisonment even exists in Equestria. It seems like a sort of societal universal, but at least at this stage in the show perhaps it's not necessary to criminally punish ponies. In fact, even after Discord I think it will be a while before we see a criminal or wrongdoing pony. 
> I think Celestia certainly is a powerful monarch, with absolute power on paper, but perhaps delegates/treaties govern Equestria in a slightly "confederal" structure. This goes into somewhat later season contexts though. I think she has that type of power even if she doesn't always use it in practice.
The fact that Luna is a co-ruler already hints at that federal/confederal structure, so I agree there. Plus I think with her absolutism, negative interpretations of Celestia obviously emphasize it but even if we take the most charitable and positive interpretation of Celestia, her subjects are so adoring of her that I cannot imagine many of them being willing to circumvent or limit or oversee any of her powers as ruler. Given her position both in the eyes of her subjects and as a being as powerful as she is, Celestia's really always going to have to exercise her own restraint in governing with a light hand no matter what. Since we clearly see that government structures are far from overbearing in Equestria, I think it's fair to say that speaks to how she prefers to govern.
> For me it has to be until proven otherwise. Considering this is Season 1, we don't really have evidence of any pony political powers with some antonomy outside of Celestia and I think it would be reasonable to assume all ponies are her subjects. 
I would agree, but for the attention given to Appleoosa's flag and their ability to essentially start a war with the Buffalo without consulting any higher official. If they are part of Equestria, it's on paper and not so much in reality, they're clearly extremely autonomous. I see Appleloosa as like an unincorporated territory.