Yep. Powercreep sucks. And Sadly, I don't think it will or can change. Someone on the discord says it's a monster devs themselves can't tame anymore. I like this image.

Yep². Nidhogg is a limited gacha unit. She is not available currently but she will be. Later. When devs will decide.
At first sight, I didn't think she would be that OP. But she is. With the right support, she steamroll all the Hraesvelgr stages (current hardest stuff where it's advised to bring alternative team styles). For me, she is the second best girl after Adlay.

R-medals exchange didn't add more regular gacha girls. Still locked on 2020. The other two are R-medal exclusive girls. Here is the list of exclusive R-medals girls : https://flowerknight.fandom.com/wiki...Rainbow_Medals. Pavonia is the best and only top tier here. The others are ok to awful. But there is good waifu material.

Well, despite the pityful state of the gacha and meta, the game is still fun and there is still potential to have fun on everyday missions and lower level content with girls out of the S++ uber meta top tier.