Marshall

Also like what about air walk or gentle criminals quirk. I feel like this was less a list about really good mobility quirks and more about the mobility quirks of main characters

Here's the thing. He could have one, but he shouldn't. Shanks is cool because his haki puts him on par and even stronger than a lot of devil fruit users. Giving him one would kinda ruin the flare

Ha! The cyclons MAYBE have a fighting chance against 40k space marines but the rest of these armies would get rolled over easy. Spartans for example while are super soldiers, are not genetically and biologically engineered to the same extent as the astartes. One space marine would be able to take on at least 6 Spartans by himself before falling. Also space marines number in the tens of thousands.