Blaze damage is proportional to the amount of knockback on each affected mob. That being said...
Quote from wolfram;80783:
I have found that 2+blaze gives the most damage and is my opening attack sequence.
If a monster is charging at you, its best to load defense. Get hit in defense, then proceed to use 2+blaze.
Trying to use Blaze to trump a charging enemy is not only hard, but creates a significant loss of damage with higher MP/SP usage.
2+Blaze
IB+IB+Blaze
FB+Blaze (against a wall)
Pushback+Closerange Charge+Blaze
Ice Spear+Blaze
...are all really good solo tactics. Fireball is bad because it can scatter mobs too much if aimed poorly. Thunder stun doesn't add any knockback, meaning no additional damage, and the following bolts may also cause bounceback and get you killed. Both are sub-par choices.
For party/pet play, any knockback skill works. In particular...
Smash+Blaze
Magnum+Blaze
Firebolt+Blaze
Windmill+Blaze
Blaze+Blaze (lol)
..are what I find the most effective.
Full charge shots should
most of the time never be used in solo play (sans Ice Spear) because you'll actually lose out on damage.
On the other hand, Ice Spear+Blaze is incredibly hard to follow up on if you don't kill everything. Blaze will leave you unable to move, while Ice Spear will grab all the aggro. Redown from the Blaze explosion also shortens the stun time on the mobs, which can get really messy. Personally, I prefer the 20% damage bonus from Combat Wands, especially since they can be upgraded to 51 max or 46 crit for some melee power.