Megatron has no sympathy; he is not affected by the terror of those whom he conquers (except to sneer at it or revel in it). However, Starscream has hit a nerve, so to speak, but Starscream sort of has it backwards. As Megatron says, it's not that he wanted to save the poor creatures out of pity, he wanted them alive to tell someone else about the great and terrible things that happened. But that in itself is a double-edged sword, as he wonders ("Am I making Cybertron a target?"). It's interesting to see Megatron's inner thoughts about what he's doing.

Thundercracker and Skywarp are very well painted, too--the 'heavies' of the trine, as opposed to Starscream's more refined perspective. They just want to shoot something. Starscream's not opposed to a bit of mayhem for mayhem's sake either but he's trying (as always) to out-command the commander, by yowling about conserving energy and whatnot.

Speaking of, you've got Starscream spot on, from his arrogance to his cowardice (turning on a dime to save his own hide) and to his ability to get periodic digs into Megatron. He's a manipulative little cuss, as always, and can push Megatron's buttons like no one else.

"They will die with amongst the ruins of our ruination."

I know what you're trying to say ("our 'scorched-earth' tactics will leave them without anything to sustain life") but it's a bit on the wonky side. But you probably knew that. =)