Giygas' profile assumes he's planet level during Earthbound Begininnings (as Giegue) which seems to be because he "altered the entire Earth with his presence alone". However, not only is this not shown (we only know he altered the game's area, which is far smaller than the entire planet) but his alterations were stuff like mind control, animating inanimate objects, raising the dead and smaller-scale reality-warping feats, rather than AP stuff.
The same can be said for Maria. She's put at planet level without any real reasoning. I'm assuming it's because she created/destroyed Magicant, but it's obviously far smaller than a planet.
This map could give us the correct area of effect of Giegue's influence if anyone would please see how big it is (There's a key at the bottom left of it). I wouldn't want to make any wrong assumptions about it's size. We could then use that value to pixel scale the overworld map somehow (comparing the size of the desert maybe? Idk, it seems a bit inconsistent. Especially since there's another official map too ) and compare it to Maria's Magicant , figuring out just how much she created/destroyed.