Dunno if this will come in handy but, from what I saw in the Media Tour videos from youtubers hands on the job, there are some details about these Weaponskills behaviors.

Drill and Air Anchor may be Weaponskills that don't share theirs recast timers with the other ones, but they are not Empyreal Arrow.
When you use a Weaponskill, Drill and Air Anchor will enter on a 2.5 or so seconds CD. And upon using them all the other Weaponskills will enter in CD for the same 2.5 or so seconds.

They are not intended to be weaved between Heat Blasts. Drill and Air Anchor also cycle when you use Heat Blast.

The only thing that can be weaved inbetween Heat Blasts are abilities.

Gauss Round and Ricochet may be the only ones really forced to be used during the speed phase, but so long they don't overcap there is no need to rush their use either.
As the ShB MCH will technically be a Ranged Fell Cleave spammer with this, you only have to push 1 button till the end of times and maybe other 2 for the sake of not overcaping (maybe more but for other reasons). This should aleviate the skill input queue somewhat to my understanding... will not bet too much on it.

Wildfire at least seems to equal to exclusive Heat Blast spamming.