"The first film is basically Doc Holliday."

The decision was made by the DEO/government, but they said it was a last resort. If Supergirl could defeat Rhea in combat and win that way, great. But if it looked like that wasn't going to happen, or Rhea would cheat her way out of the duel, they told Supergirl to go ahead and set off the bomb.

I don't read a lot of Superman comics but I remember this being mentioned somewhere to explain his disappearing clothes and how he gets them back when he changes back from Superman to Clark.

Right, it's coming back to me now. So they didn't deliberately destroy the planet, but their actions destabilized the planet. So they weren't specifically trying to destroy Daxam. So while Krypton should shoulder some of the blame, individual Kryptonians like Superman and Supergirl, who had nothing to do with it,…

I doubt the Daxamites would accept Mon-El even if he tried to lead them. They all know that he rebuffed his parents and allied himself with the people that killed their queen. They might have tried to kill him on sight.

Supergirl can't fly to other planets any time she wants. It's been established in this show that she can't breathe in outer space.

Considering how much this season of Legends of Tomorrow improved over last season, it's hard to take your opinion on anything seriously when you say that show should be cancelled. It was the best CW superhero show this past season, no contest.

"the Daxamites are also refugees, and what's more, that this is only the case because of Krypton's actions."

Superman has been fighting villains for 10 years on this show, but he has no official fighting experience. All of his fighting skills are self-taught, learned "on the job".

You do realize this is a show with an alien that travels to Earth and gets superpowers from the sun, right?

Depending on what comic book era you read, sometimes the writers say Supergirl is stronger, others say they're equal, and others say Superman is stronger.

"this whole season she - and the show itself - has done a decent job of espousing tolerance and alternative/non-violent ways to settle problems."

"if she had the mind-controlling silver kryptonite, did Rhea not use it on Kara as well?" As David Phelps said, Rhea knew it would make Superman see his greatest enemy (Zod) but who is Supergirl's greatest enemy? At this moment it's probably Rhea, so what would be the point of using this kryptonite on her?

Whether or not Superman is strong than Supergirl or vice versa (depending on what decade you're reading the comics, the answer is different), the Supergirl on this show is a better fighter than Superman. He has been fighting villains for 10 years but he has no formal training. Kara has spent 2 years being training…

Leena: Are those your Daxamite ships?
Rhea: Yes. They're real, and they're spectacular.

She wore a raspberry beret.

"irradiate the atmosphere with lead? 'Irradiate' means 'expose to radiation' and lead isn't radioactive" In the comics it was "lead radiation" that was lethal to Daxamites, not just exposure to lead. So the "irradiate" was likely a nod to the comics. As for the rest of your question about exposing the atmosphere to…

When Lillian showed up in the bar during the invasion, she knew that the good guys would be so busy fighting the Daxamites that they wouldn't have time to fight her and Cadmus. Same reason why they didn't tell the President to step down once they realized she was an alien - "Let's wait until after we stop the alien…

I'll allow it because it let them have the line of Kara apologizing to Superman for destroying Kelex. "Sorry."

In Cat's defense, she figured it out in the first season, but having Kara and Supergirl both in front of her made her think "I guess I was wrong". Once J'onn's identity (and abilities) became public, and she became aware of the existence of other shapeshifters, she (apparently) realized that she had been fooled.