The interesting thing about this is that, for Starscream to have all the time and opportunity to plot and attempt to assassinate/undermine Megatron, he must be incredibly efficient at his main job as well.
So, what is his “job”? Destroying Autobots, of course. But you can only battle so long, and being second in command has to come with a lot of admin work, too.
My headcanon is now that Starscream is actually, despite all expectations, freaking excellent at managing people. He sees through you, dude. He knows what you want. He knows how to train, pay, bribe, and encourage you so that you will do your damn job with the minimum of effort from him. He knows this for everyone, and he will treat everyone utterly differently. He’ll bitch and yell at some people, communicate with others via email, praise some for every little thing, never praise others, and his duty rosters are utter chaos because he knows exactly who to put on shift with who else and there is little rhyme or reason to it unless you know who distracts who, who likes who, who hates who, who will help who.