I always been to Melaka when going back to Muar. Y a Singaporean want to visit the shopping mall when they have a better mall. Tourist over there only keen on local food and heritage building, there's nothing do with the shopping mall.
With the population of Melaka, may be 1 or 2 malls are sustainable. IMO, Dataran Pahlawan & Aeon Bandaraya doing ok. Mahkota Parade so so and Hatten Square is a gone case