Considering that Kizaru is likely setting the bar for such speeds in One Piece for the later arcs and high tiers, it would not be an outlier, and is still far from comparing to Kizaru's light-speed.
And the calculation has nothing to push away from Doflamingo actually proving such speed given that we saw the meteorite before and after Doflamingo's assault on it.
Meanwhile, Luffy's relativistic calculation is impossible to prove due to 3 factors: 1) Aim-dodging, 2) hyperbole for laser speed, and 3) we never saw the beam and Luffy on the same panel until after Luffy had already dodged it.
Characters that I can think of who scale to this:
Doflamingo(duh), Trafalgar Law, Luffy, Sanji (fought Doflamingo), Zoro (equal to Sanji), Vergo (fought Sanji, and fought Law), High Executives (scaling to Vergo and Doflamingo), Chinjao (fought Luffy), Lao G (fought and bested Chinjao), Sai, Ideo, Dellinger, rest of Executives, Cavendish (blitzed Dellinger), Admirals, Sabo, Ace, Blackbeard, Whitebeard, Garp, Rayleigh, Gold Roger and that's all I can think of who can full on scale to this... Some of the Strawhats can scale to this, i believe.
Punk Hazard and future arcs scale from this due to Doflamingo and Law.
@Lina - MHS is supported by Kalifa pre time-skip for reacting to and defending against Lightning from several meters away. Punk Hazard and later scale to Doflamingo's speed feat.