With the stats as they are now, the beast possible order would be exchangers>vents>destruction, because then the exchangers would always be moving as much heat as possible into the vents and as long as the vents could keep up they would not need the storage.
@vts6482 I'm not sure what your talking about, but I'm assuming heat vents are calculated on an individual basis, and I've seen no heat vent output more than it can hold. However, I have seen heat vents stay at 0 heat while cooling cells fill up and melt (all connected by exchangers of course.)
HINT ON LAST PUZZLE:
Go at it with the idea of the existence of the characters you are working with, once I started thinking of it like that it was a piece of cake.
So after about 2-minutes of lying face down on the pavement my guy randomly starts having seizures and manages to jump at the beer bottle he seemed incapably of reaching before... lolz