Shaula's magic needles will naturally scale to Hakugei magical durability. It is magic based because only EMT could stop the needle flying and make it fall to the ground.
Since Shaula can get through Hakugei's magical barrier, and magic attacks need at least Town level AP to hurt Hakugei, her AP would scale to the capability to damage someone with Town level durabilities. The attack is an explosion-vaporization type rather than something like swords.
At worst she's MCB to Small Town for taking a few seconds to get through Emilia's six layers of ice walls, in instant if it's one layer. Emilia was only stalemating because she was creating so many, but even then was still losing the firepower match up.
So I think Town level AP to hurt someone with Town level Durability, like Hakugei, is reasonable for Shaula. If she was only Building level physical then she would have been no threat to Emilia.
About the White Whale:
I am not saying he is 100 kph. I am saying he is moving very fast in a scene where the 100 kph Patrasche looks like she's crawling at 10 kph.
Dodging-by-moving feat during combat, and travel speed, are handled differently. We know a lot of people, like Guts, are Hypersonic, but that's not the speed at which he travels, just the speed at which he fights. Patrasche's 100 kph is also only travel speed too.
If I find the quote that says Mimi and Hetaro's attacks are sound-based, because they discovered the ability when the echoes from their chit-chat flattened their surroundings during a mountain hike, we can already get the timeframe for how long it took Hakugei to dodge the Mach 1 projectile (that was aimed at something else but Hakugei thought was coming at him).
We can also use this vid to calc the time he needs to cross his own length for his travel speed... but it's already obvious by eyeball, I just feel very lazy because we can already use the vids for source.
https://www.youtube.com/watch?v=HEyobbaO-AM