I feel that I'm not really understanding what Boost is originally intended to do if the 10-15 second delay is actually intended.
I'm not a ridiculously geared MNK or anything (a mule with ambuscade NQ + Sparks weapon), but uh. I can have 3-4 attack rounds in the time it takes for me to land one boosted punch. Or I could Chi Blast for a couple K damage... oh wait, I could do more than 2k damage with 3-4 attack rounds, as my punches land for 200s on Apex Raptors. Okay so I can Chi Blast for ~1500 on those raptors. OR, I could land 8 punches and a kick or two for 200 each for 1600. Not seeing the point of Boost, to be honest.
Now, the Focus and Footwork changes? Oh yes. Now those I can wholly get behind. Focus is usable at the beginning of every fight just about, and Footwork can be paired with Impetus as they have the same cooldown every other fight to give a nice little hand up on damage output.
Boost? I'd say that's a complete miss.
IMO, let's just change boost to a directionless Sneak Attack and be done with it. Maybe not as dramatic as Sneak Attack, but still a similar concept. Use JA, next attack does extra damage. Boom, done, easy. This whole 10+ second delay is killing any DPS that Boost would have added. Why would I want to stand still for 10+ seconds doing nothing when I could have landed 6-8 punches in the same amount of time?