When Yuuki Yuuna wa Yuusha de Aru aired, it had already been almost 4 years since Madoka Magica. At that point I think it was no longer constructive or interesting to try to compare every magical girl show to Madoka, but in this case the similarities were too numerous to ignore. That’s not to say Yuuki Yuuna wasn’t interesting at all in its own right, but I feel like the comparison had to be made.
In both shows, a group of regular girls become magical girls and frequently go to a mysterious alternate dimension to fight mysterious enemies in order to protect the lives of the innocent. I know, I know, just this doesn’t necessarily mean Yuuki Yuuna is more similar to Madoka than to other magical girl shows, but some of the mechanics and emotional points are also very similar: Both have “suffering”, and in both shows the process of fighting the enemies can have drastic negative effects on the magical girls (beside the risk of dying, of course).
But take that as you will. I imagine some will see fewer similarities, and others will see more, maybe it doesn’t matter that much, because in the end the show is not just a copy of something else. It was, in fact, a show in its own right. It had an emotional climax (in either ep 9 or 10, I forget) which was pretty fantastic in my opinion, but it also had an ending that resolved basically nothing, which was the reason I ended up disliking the story as a whole. And the ending is wholly on Yuuki Yuuna, it’s not the result or fault of any “copying” from another show.