Are your legs too short for effective triangles against larger opponents? Without the gi, your collar chokes from the guard have disappeared. Do you have difficulty with actually catching anyone with the arm bar from the guard?
See : Arm Lock From The Guard
https://graciebarra.com/gb-learning/arm-lock-from-the-guard/

Let’s see how some Gracie Barra instructors use the omoplata in their games.

You might want to explore the possibilities of the omoplata. It is commonly used as a sweep, but today we are focused on how to use the omoplata as a submission. One black belt advised “If you have short legs and triangles are difficult, remember that every triangle set up can also turn into an omoplata!”

1) Omoplata from closed guard
A good place to begin looking at the omoplata is from the closed guard. Check out how the lasso hook is used to create an opening for the opposite side attack.
https://youtu.be/sT__t7U-vGM

2) Spider guard setup
The triangle and the omoplata are the best friends of the Spider guard player. Pay attention to how
Prof. Daniel Marques stretches his partner out for the setup.
https://youtu.be/eKVp7TxhgPI

3) Secondary Kimura attack from omoplata / Do omoplata para a americana
Professor Thiago Silva of Gracie Barra Paraiba teaches how you can follow up your initial omoplata attack into a Kimura lock.
https://youtu.be/_TlB1tCL9UQ

4) Omoplata to counter a reversal
You can attack omoplata from the top position as well. Professor André Deco Rachadel of Gracie Barra São José shows how he counters an escape with this variation of omoplata.
https://www.youtube.com/watch?v=3FfiGarY4Ok

5) Alternate way to finish the omoplata lock
Mestre Frederico Pimentel demonstrates an alternate way to finish the omoplata with pressure on the shoulder. Note how he disables the far arm of his opponent as well!
https://www.youtube.com/watch?v=PNbMOo8MIvU

What is YOUR favorite omoplata technique?

See also on Gracie Barra : GB Techniques: Single Leg Takedowns
https://graciebarra.com/2016/10/single-leg-takedowns/

Credits: Mark Mullen
Gracie Barra Black belt based in Saigon, Vietnam
Instagram: facebook.com/markmullenbjj