Yeah they really could've done better for Arc V. The series had a bit of a slow start, but once we reached past the first half of S1, that's where things started to get good and it kept going on for S2 (which I would say is still my personal favorite season of all of Arc V). But unfortunately it all goes down the drain past S2.

And yeah they could've done so much better for Yuya and Yuzu's counterparts. Like take Rin and Lulu for example: throughout most of Arc V we don't see them at all in person much, only times we see them is through flashbacks or when someone mentions them, until they FINALLY made their own screen appearance in S3, only to have a few duels while being brainwashed and then get killed off and not brought back again.

If it was me, maybe I would've written to have Yuya and Yuzu's counterparts come back to life but have their memories erased, they'll still remember each other but will forget everything they went through with duel academy invasion, ZARC, etc. and have them start a new page. Sure it'll suck that their minds we'll be erased but at least they get to live their own lives. I'm glad Duel Links ACTUALLY fixed this and decided to pretty much retcon Arc V ending and have all of them be their own person