I really like how the starter characters always seem to be featured arena characters. Makes upgrading them theoretically a great investment. They're bad, but they shouldn't be so bad you can't win with them at all on offense with an otherwise good team.
Now if they would just stop featuring Takumi we could shake up the meta a bit, although I see the benefit of repeatedly featuring the five-stars from the special event to include more people.
I've been realizing that the main thing I have trouble against is, fairly unsurprisingly, Azura. Given that she's my absolute top-ranked, number one character for Fates lunatic and if anything she's even more powerful in Heroes, that's gotta be expected. Now I guess I just need to focus on figuring out how to consistently bait her into making bad plays. It should be possible on most maps at least.
Meanwhile I've got enough feathers that I can take my four-star female Corrin (upgraded fron a three-star) up to five stars next week. Maybe not the most optimal use of feathers, but I love how well she and Camilla work together.