Some thoughts. I liked Part 2 better than part 1, but I feel that their efforts to be so inclusive led them to make some choices that are harder because of the universes they are playing in.
For example--Smallville. I have absolutely no problem with an Earth where Superman gives up his powers to have a family. However, I do have an issue with SMALLVILLE Superman doing that. Why? Because we spent 10 years watching Clark's journey to become Superman, and it makes absolutely zero sense that he would go through all that only to give it up. We learned the lesson in Superman II that Clark can't afford to be that selfish, and one of the things that makes Superman so special is that he knows that his abilities give him a chance to help so many people. The world will always need him so to have him give it all up is so out of character.
And this version of Clark should realize this lesson, as his intro to the world had him take on APOKOLIPS.
Even with other heroes to help, Clark is a leader, and not the type of person to let someone else put things on the line when he can do the same and better.
That's not Superman. Plus, he really took a whole nonchalant attitude toward the fact that his world and family are in danger. Even ignoring the COIE, Clark giving up his powers would PUT his family in danger as it is inevitable that someone would find out who he was and take revenge.
However, if we see Welling again, I think we have a great story. His life paralleled the Reeve Superman in many ways. Reeve's Superman also tried to give it all up for a life with Lois, but immediately was shown that he couldn't. Superman is too good of a person to sit back and give up his ability to help so many people. Had Superman not been able to get his powers back in Superman II, Clark couldn't have lived with himself as Zod ruled Earth.
As a finale for Smallville, Clark giving up his powers is awful. Great to see him happy, but it's very un-Superman like. As a STORY for Smallville, that's different. I wish they could have had Welling realize this situation and convince him to try to get his abilities back. Plus, I wish he could have spent more time with Hoschlin's version.
A similar issue could be said about Routh's Superman.
The intent is clearly to have Routh be the Reeve version and I get that to an extent. They even did a subtle thing that I loved, which was have his heat vision be red.
But they have a similar issue that I had with Smallville. I have absolutely no issue with Kingdom Come Superman existing. But to have him be the REEVE version is a terrible situation for the audience in my opinion.
Do we really want Christopher Reeve's version to go through all that?
But is this really the REEVE version? Or the Routh version? It's a little more acceptable if you separate Reeve and Routh, even if the movie didn't specifically do that. If you think about it, Reeve and Routh were very different. Reeve's version was much stronger than Routh's mentally.
Reeve's version was well educated on Krypton and ESPECIALLY after the events of Superman II, would NEVER leave Earth for a period of years, and even if he did, he would not be a chicken and not say goodbye to Lois.
Plus, we know for a fact that if the Joker set off a bomb in the Daily Planet killing everyone Clark cared about, Reeve would simply spin around the Earth and save everyone. There is no reason to believe Reeve wouldn't do that.
Routh's version was the stalker deadbeat dad. His version of Perry White was a different race. His supporting cast was also quite different.
Plus, if you factor in the real world, they marketed the Routh version has a sequel to Superman II, but ignored III and IV.
That would imply a completely different tangent.
It's a multiverse, so it could be a different Earth.
In Superman III and Superman IV, Reeve never left Earth. Clearly more than 9 months passed since Zod. So he couldn't have got Lois pregnant. Plus, in the Routh version, if it followed Superman II, then Lois would have been pregnant with no memory of how she got that way.
Another issue.
Anyway, it works a little better if Routh's version and Reeve's version come from similar Earths but not the same Earth.
I would just find it harder if the REEVE Supreman lost Lois that way, and again, he would never allow it.
The only issue is the line about Superman fighting himself, but in the Routh version, if Superman III never happened, perhaps a similar incident happened after the events of Superman Returns.
So basically, in both the Smallville and Donner situations, the Supermen we met were fine, but they didn't work so well as actually sequels to THOSE characters that we followed.
Regarding BATMAN--here's where they got it right. Earths are Earths. I have no problem with Bruce turning rotten on an Earth. Here, we have an Earth with no continuity or past. So anything goes.
This version of Bruce isn't a good version. The version of the main Arrowverse has to be better. Hopefully younger as well. I'd like to see someone who will become the man that trains Terry McGuiness. Of course, that would be many years in the future, and would only work in a show set in the far future.
Back to Routh, I feel there is debate as to whether Routh is the Donner Superman, the Superman Returns version (assuming he's different) or a third version, all from similar but not identical Earths.
But either way, I want to see more of him and I hope they give him a meatier role in the next few episodes.