Barodahn:
Hyper Speed seems really unwieldy...bonuses to hit that don't help with damage just aren't part of the system.
And you should go with whichever version of the guy seems most reasonable.
wyvern:
That's just not how it works. All Powers in OW are completely canon as acceptable powers. The stat blocks are speculative and debatable (like Kumori's lack of Lawbreaker, which is actually just a minor error on Evil Hat's part), but the Powers and Stunts were all designed by the exact same people who wrote up those in the core book and are every bit as canonical.
But even leaving that aside, check out Inhuman Strength:
+2 damage. Flat, stacks with other effects. Worth two or three Stunts right there. Call it 2 1/2. Actually, more like 5 since it applies to all Weapons and Fists attacks.
+3 to Might for lifting. Very explicitly 1 1/2 Stunts.
+1 to Might for Grappling. 1 Stunt.
Might always adds to other skills. Not really a Stunt effect, but call it 1 1/2 Stunts based on it being better than Supreme Concentration.
That's 9 Stunts of stuff for -2 Refresh.
Now assuming two Stunts to shift an entire Dodge trapping (sounds about right), A Few Seconds Ahead is worth 4. Or less than half as many. Now, Inhuman Strength is indisputably one of the better -2 Refresh powers, and A Few Seconds Ahead indisputably a very good -1 Refresh power...but not outside the realm of what's allowed.
Now, the list of skills Wide Experience can grant is basically as follows: Conviction, Deceit, Discipline, Empathy, Intimidation, Investigation, Lore, Performance, Presence, Rapport, Survival.
Now, of those, barring Rapport, none have more than 5 Trappings (and usually, transferring a Trapping is one Stunt), and most 4 or less, so adding them is indisputably not too bad. The four best are Discipline (wich at three trappings, one a Dodge trapping, is worth 4), Deceit (5 Trappings), Empathy (4 Trappings, one a Dodge trapping, so effectively 5), and Rapport (5 Trappings, one Dodge Trapping, so effectively 6). Now those would be potentially unbalancing, looking at them...which is where that -1 comes in as a very nice balancing factor.