Seeing as SAO basically spawned the era of Isekai and RPG-based anime (Even if Reki is adamant about the fact he didn’t), there’s definitely some other anime stuff similar to SAO.
For concepts similar to SAO, as in the full dive mechanic, I would have to say that the few that come to mind are:
“Seven Senses of the Re’Union”
“Bofuri: I Don't Want to Get Hurt, So I'll Max Out My Defense”
“Full Dive: This Ultimate Next-Gen Full Dive RPG Is Even Shittier than Real Life!”
“Log Horizon”
I’ve watched all of these except for Log Horizon, but that’s the one that I would say sounds the most similar to the Aincrad arc. It’s also one of those series that is said to be SAO done right (Even if it’s third season that released around the same time SAO’s third season finished wasn’t as well received or talked about like SAO’s). Seven Senses of the Re’Union is one that is the most emotional of the bunch and was compared to a mix of SAO with Anohana (If you haven’t watched that anime, you should. It’s an amazing slice of life anime made by A-1). Finally, the other two are comedies. You might even find some similarities between the shows.
I’m sure there are more, but those are the ones I can think of right now. Apart from Log Horizon they’re all relatively short. I’m pretty sure they have on season and are around 12 episodes long while log horizon had three seasons with season 1 and 2 being 24 episodes long and season three being 12.
Anyway, yeah, you are finally reaching the end of the anime adaptations for Reki’s work. But there’s plenty more novels and short/side stories. More than I even knew existed. I had done some quick research to try to compile every title into a document as a sort of check off list, but I quickly realized Reki really has written a lot of things. Currently I have counted 96 different novels/short stories and I’m still missing a few more (Plus some more of his upcoming volumes). Some of the things are pretty obscure and you really need to do some digging to find since it’s not officially published and only have fan-translations. Thankfully I was able to spend some free time looking for these stories and found quite a few if not most of them, downloading the PDF versions of them. I even had to resort to an internet archive to find some of these stories that seemingly no one had an English translation to.
If you ever need any of these, I could send them to you if you don’t feel like looking for them (Which I wouldn’t blame you). I could send it through discord at some point (If that’s even possible, I don’t use discord much so IDK), probably after you finish the AW anime (That would also give me time to look for more opportunities to find the other SAO stories)
As for Megumi’s character, you will be getting more about her later in the novels (much later). For now, I see this as a good introduction to her character and the purpose she will serve later.
I don’t know why but I had never paid too much attention to those character from the Kuroyukijime story. Even the fact that he was a screw and that detail of his parents being divorced flew right over my head till you pointed it out. I do hope Reki brings those characters back since I feel like he could explore their lives a lot more. Seeing as the novels are at an interesting point, I feel like it would be great to see those three in the main plot some more.
Something random I just thought about was the fact that the kings of pure color don’t appear that much in the anime. They do become much more prevalent later on though.
I hope you can get to the novels soon enough. I don’t really know how you are going to have that all set up but I can’t wait for it.
Now for a fun fact. This one is less about SAO or AW but it is part related. Recently, a popular manga artist began working on a new series in the Isekai genre. It had a group of characters that were all from another world and were completely overpowered. Among these, and the leader of the group, was a dual wielding swordsman who wore all black and used a blue and black sword. His name was Kiruto (Sounds a little similar to someone else). The rest of the group was filled with characters that very closely resembled other characters from popular series like Overlord, Re:Zero, Reincarnated as a slime, and many others. The only difference being that this group was evil.
Well, believe it or not, fans were pretty outraged at the whole situation which led to the series being cancelled after only releasing 1 chapter.
If you ever want to check out this series the name of it is Isekai Tenseisha Goroshi -Cheat Slayer- (Killing the People Reincarnated into the Other World -Cheat Slayer-)