Well, to be fair to Louise, it was the aliens' influence that made her do it. It's not like her high faith gives her any chance at resisting in any meaningful way.
Access to Pokemon is restricted to one-way summoning, the only way Rayquaza is going home is if Poke-God summons him back. Which is actually a 1 percent chance every chapter as long as Rayquaza is alive.
Individual travel to a Prince's realm. Easy. Mass transit access via Gate? Requires permission in the form of the Prince's sigil on the sigil stone, which is incidentally why they're called sigil stones.
As for a Daedric Prince liking alien? Molag Bal loves everyone and everything... in a serial murder-rapist sorta way(in that order occasionally). Mehrunes Dagon would kill them, then you, then the x-com world, then use the Oblivion gate you made to reinforce his position in Halkeginia to aid in defeating Hircine for dominion of that world. Hircine himself would like the challenge and is the Lord you have the best chance at dealing with in most situations, as he is one of the reachmen's gods. Sanguine would be pissed if you dumped them into any of his party realms. Hermaus Mora would enjoy adding their knowledge to his collection. Meridia would kill you without hesitation. Azura doesn't like when unexpected things happen. Malacath would likely aid the aliens for your trickery. The Nurgle-Dragon Peryite could go either way. Mephala would probably be ok with it, but you might find an ethereal invasion fleet turning up in some unexpected important battle later on. Vaermina would feast on their minds. Nocturnal potentially predates the TES universe and is unknowable by nature. Uncle Sheo... who can say, really?
