100%-70% look fine. Your upscale is 200%, that's why it looks cleaner (since it's exactly four pixels per single pixel of the original image). Exactly 200% is unrealistic in practice.
Also keep in mind that with larger sprites (the way I say it should be) the 100% one would be on screen for most of the time. Lower percentages would only come up when moving back to show some attacks. With yours it's the ~200% that's showing almost all the time.
The scaling mine uses is perfectly within the capabilities of the DS. Also the default sprite size would be about the size of the largest Charizard in the last image I posted, so the small features like the eyes and teeth will have more pixels available to them in the smaller size, so would look even better then this.
I can't believe you think upscaling looks better than downscaling. Oh, and pixelation isn't less noticeable with motion. After all, we've seen them in motion.
In 3D objects and other images? No, downscaling looks better.
In the world of pixel-art? Up-scaling (by 200%, which you say would never be used, but then you say would be used most) is far, far more attractive.
Pixel-art is supposed to be viewed pixel-by-pixel, and downscaling ruins this. If your idea made any sense,
it's what Gamefreak would be doing.
This is coming from someone who's spent over a decade now in the spriting community: Half the artists
deliberately upscale their works to 200% for better visibility.
Downscaling sprites looks horrible, just like upscaling them by anything short of 200% does. From what I can tell in screenshots, the backsprites are scaled by 200%. The pixels are perfect, and clean; they aren't distorted by the 3D engine, and this is a very important factor.
By the way, judging by the videos (which yes, we have seen in motion, and that's my point; they look great), the only time the backsprites are 200% is when you're choosing your move. You're not even looking at them during this period (and they're obscured anyway). The perfect, 100% sprites are shown during the battle animation, which you
are watching.
Oh, also, in your image the 100% sprite isn't even clean, you've damaged all of them in their entirety, which is why pixel-artists with integrity refuse to do this.
The fact of the matter is that you are adding filters that degrade the pixels, and this goes against the very point of using pixel-art.
If they wanted a system like that you would be using vectors or 3D models. Pixel-art is just that; art.
