Then you're scaling things completely off accuracy.
Sand Tsunami only has the volume of forest [
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], which isn't an impressive feat in P2, as most characters in P2 can now destroy a forest. Water Dome is both in width and height equal to a singular mountain. I posted the scan above. Mountain volume > forest volume.
Now on the meteor, lol. It's obviously not bigger than any mountain, lmao. The full meteor is the height of PS, which is the height of a singular mountain. The equation is then this:
Water Dome = singular mountain = PS = full meteor > bottom meteor = Gaara's sand which halted it > sand tsunami = forest.
Kisame has more Chakra than Gaara is based on how the author portrays Kisame's Chakra sensed by characters in contrast to Gaara's Chakra sensed by characters. Karin senses Gaara's Chakra and doesn't exaggerate anything about it, while she senses Kisame's Chakra and calls it big. Then Kisame has more Chakra based on this analogy. As for feats, apart from Water Dome, Suiton: Bakusui Shōha has greater quantity than anything Gaara showed only at 30% of his Chakra.