Ideas that rhyme are probably the best ideas.
Is there any concept too complex to be expressed in rhyming couplets?

The universe is very large.
We’re still not sure who’s in charge.

I love you a lot but it hurts a lot too;
The pain is worth it for the pleasure of you.

If you want a pet rabbit you have to buy two
Because they get lonely despite living with you.

I don’t know if there’s a god that lives in the sky
But it’s good to be good– search for how, not for why.

Some lives are long and for some the time flies
Any which way, everyone dies.

Money is important but it’s not the main thing.
Pennies buy independence but greed is a sin.

When building a building best to start from the ground.
The roof goes on top and the walls go around.

If you need any more advice, just let me know.