I can't figure out if the writers want us to forget that we already saw a Legion Flight Ring in Superman's Fortress of Solitude, meaning that he's met them before and that they had to have existed BEFORE Mon-El went to the future, or if they themselves have forgotten that fact, but it's a little weird.
No continuity. That, and as mentioned yesterday, the origin of the Legion has been altered from the comic source.
I don't know about anybody else, but I love James and Lena together, romantically or otherwise; I also love that James has a portable Guardian shield, although where he keeps it is a question I don't think we'll ever get the answer to.
I don't see it as a real union. Somewhere along the way, I expect Lena will cross some line that James cannot stand for (criminal, etc.), or he will only be used as wedge between Kara and Lena when he's forced to choose a side in some conflict.
I think there is a big reason why TPTB won't bring Superman in: it is a very feminist show that is all about Girl Power. Heck, the only time they did bring Superman in, it was to make Supergirl look good. They are going to want the story to be about Supergirl and how she saves the day.
That is the great failing of this series, as its buried in a misandrist agenda, painting a world where only women either hold any position of power, while all males are reduced to weaker positions (in any category), hence the
one time in film history where Superman has been reduced to a weaker, indecisive third leg, with Winn stammering through life, easily rattled/threatened, and James...well that's another story.
Notice how this kind of unrealistic one-sided "world building" was not necessary in
Batman v. Superman: Dawn of Justice / Justice League, where Wonder Woman did not need to be made superior to Superman in order to appear powerful/wise. Like the
comics, female characters stand out
like all others, but not at the expense of male characters. The same applies to the MCU, where characters such as Wanda and Valkyrie are formidable--but they operate on their own terms, defining themselves, without any need for the producers to constantly reduce their male counterparts to weak and or ineffectual background players in an attempt to raise their profiles as heroines or characters of importance. .
If they do bring him in, it will be for Reign to kick his butt and have Supergirl save him.
I would not be at all surprised.
I would hate that but it is my prediction. I hope I am wrong because I do think that from an in-universe point of view, Superman should be involved.
Not only Superman, but J'onn as well. Yes, this is only "round one" in the Reign plot, but J'onn completely out of the conflict was a typical example of what you observed about this series. One of the reasons why this version of DC characters are barely taken seriously. Either the characters are the characters, or they are a pack of "in name only" bit players.