Revolution repeated summons me soonest—what am I?

These are probably wrong but here are some ideas I've had revolving around....

Could it be something like

Dethrone the king, cast out the poorest
Revolution repeated summons me soonest

Put the rocks in the sky and the sun in the sea
Either way 'round, I'll still be me

I am (mostly) in crabs, and fish, and in birds
This way I am myself in these very words

Fastest in each of a metronome's flicks
And part of its tastiest ticks

Is it?

Dethrone the king, cast out the poorest

Revolution repeated summons me soonest

Put the rocks in the sky and the sun in the sea

Either way 'round, I'll still be me

I am (mostly) in crabs, and fish, and in bird
This way I am myself in these very words

Fastest in each of a metronome's flicks
And part of its tastiest ticks