vhelblings

That's true. But they won't tell everyone right away.

Something like that is the plan.

He will create everything himself.

Yes

As soon as I get more ideas

Of course. But doing so would reveal his power. And he will use it as a 'surprise'

This one is dead, like completely. He has absorbed all of the energy completely. The others whose shards he uses as fuel for weapons and the like are still 'alive' in the C'tan sense.

This one's good.

You are correct, he has virtually limitless access to new Necrons, but they don't have souls. I don't know whether Cybertronians have souls, but the Necrons surely won't.