So far, it appears that James Gunn has learned much from the MCU. He's largely steered clear of the mistakes that have plagued that franchise for his own DCU, primarily when it comes to television. There hasn't been an oversaturation of content, as there was in 2022 when there were three MCU films and three MCU Disney+ series.
And the series that have come out – Peacemaker, Creature Commandos, and, presumably, the upcoming Lanterns– are supplementary pieces, not mandatory shows to watch in order to understand what's happening on the film side. But if there is a must-watch, it's the 4-part Krypto Saves the Day!, a series of four shorts featuring the breakout character of 2025's Superman.