I like the ambition of combining Pong and Breakout, but games with the same premise, such as Destructure: Among Debris, and Twin Breaker, try their best to make the combination of the two games more nuanced. They feel so much more than just a direct combo of the two classics, since they add a lot more features and mechanics (and their own flavor of visuals) to create a tasty mixture.
There's all kinds of possibilities of what you could try with your game, whether it be upgrades or various enemy types, or potentially completely different mechanics to use. Maybe each level scrolls horizontally and the player tries to break as many blocks as they can while they scroll to the side, revealing more blocks and potentially other mechanics or obstacles. I think this is a good base that you can work off from, experiment and see what you can come up with!