I Better Let You Get Back to Work

I Better Let You Get Back to Work
 

To end a conversation, I wanted to say: I better let you get back to work.

Now that I have had time to think about it, are any of these viable and/or correct options?

Más me vale dejarte volver a trabajar
Más vale que (yo) te deje volver a trabajar

Mejor te dejo volver a trabajar
Será mejor que te deje volver a trabajar

Thanks in advance for any input, corrections, and explanations.

All your sentences are grammatically correct. :)

I'd prefer "más me vale que" for a situation in which you are evidently threatened or there is an obvious consequence if you don't do otherwise. Maybe you're seeing the other person getting uncomfortable talking to you, or a boss approaching to scold you for not working.
Some examples:
- Más te vale que la casa esté limpia cuando llegue. -> You'll face consequences if the house is still dirty when I'm back home.
- Más le vale al gobernador cumplir sus promesas. -> The people will react if the governor doesn't keep his promises.
- Más me vale salir corriendo. -> Something bad will happen to me if I don't rush out now.

A more common way to say it: "Bueno, mejor te dejo seguir trabajando". ;)

Thank you, AngelicadeAlquezar.