The heat vents don't scale with the exchangers for the simple reason that if you had a vent that lowered heat by 2 mill/tick, and an exchanger that moved heat by 2mill/tick then you would never have the need for exchangers.
The only thing I don't like about this game is that the longest I've ever survived is 101 seconds to level 10. At that point, when you can't level up anymore, the game gets a bit repetitive. In case you were wondering how to get that far, I used mostly falcons, and made sure I always had at least one lion to make sure I got the most DPS out of the max ships I could place. Once I get to the higher levels I start placing down turrets to soak damage and take the bulk of the damage off my reactor. Bombs get more and more useful as the density of the ships increases.
Here's a tip, if you keep your cursor near the center, you can move your gun much, much quicker. Also, why are you complaining about the bullets going through the balls? That's because you shot a power-up.
"Sir! Our enemy has only one cannon on board with a slow cooldown!"
"Walk in groups of one at a constant pace in a straight line all the way to his ship"
"But sir?"
"I SAID WALK!!!"
This game stopped being fun for me when I realized that you can actually time it so the die lands on the number that you want. Now I'm not an expert at timing, but I can make 100% sure it will NOT land on 1, so I can make sure that I kill everything in one hit.
Bug: You get 10,000 bonus if you immediately press the down key to shut off the engines right after launch. It gives you the "ACE" Achievement, for not hitting anything for 10,000 meters.
Just so you all know, the boost can only be used during the arrows main flight, that means if you start to decline, you can't use the boost anymore. The boost is used with the left click and the arrow is controlled with the mouse.