While immersion anywhere in Maa Ganga within Kashi is highly meritorious, Manikarnika Ghat, being the Mahashamshan (great cremation ground), holds a unique and profound connection to death and liberation. It is believed that Lord Shiva and Mata Parvati themselves frequent this ghat, offering Moksha directly. Immersion here is thought to be particularly potent for breaking the cycle of rebirth.
Other ghats like Assi, Dashashwamedh, Harishchandra, etc., are also perfectly auspicious. Ganga Maiya’s grace is present everywhere. The choice might depend on accessibility, the Pandit’s tradition, crowd levels, or personal preference. The core benefit of liberation through the Ganga in Kashi is available at all major ghats.