First, I'll try to calculate Pantherlily's Speed feat (while he was boosted by Wendy) from chapter 214 here. Wish me luck.

Pantherlily's Height = 115px = 1.93 meters

Explosion's Radius = 107px = 1.796 meters

The distance Pantherlily traveled = 595px = at least 9.986 meters

9.986/1.796 = 5.56 (Pantherlily was moving 5.56 times faster than the explosion)

"Typical detonation velocities in gases range from 1800 m/s to 3000 m/sTypical velocities in solid explosives often range beyond 4000 m/s to 10300 m/s".

Assuming the explosion's detonation velocity is 1,800 m/s: 1,800 m/s x 5.56 = 10,008 m/s (or Mach 29.17)

Assuming the explosion's detonation velocity is 3,000 m/s: 3,000 m/s x 5.56 = 16,680 m/s (or Mach 48.63)

Average = 29.17 + 48.63 = 77.8                 77.8/2 = Mach 38.9

That's High Hypersonic. Azuma was able to dodge Pantherlily quite comfortably, so that means he (and anyone who is as fast as him / faster) should also be at least High Hypersonic. 

Now, Pre-First Timeskip Erza (who is considered Hypersonic+ without buffs here) and Pre-First Timeskip Gray with Wendy's buffs > Pantherlily with Wendy's buffs.

Purehito (while holding back) dodged both of them casually

Pre-First Timeskip Laxus was able to blitz and tag a more serious Hades multiple times.

Now I'm not a scientist and I only know the basics so I guess this is as far as I can calculate unfortunately. I still don't know how fast Purehito had to be to dodge two High Hypersonic characters as casually as did and how fast Laxus had to be to blitz him to the extent he did.

So what do you think guys? Was my calc any good? And if someone could maybe answer the questions I have that's be great as well. ^_^