I grew up with a thick Australian accent with a drawl I dislike, and have been consciously trying to change it for a while. The problem is I tried to make it sound more American at first but keep getting drawn to speaking "Britishly". Now it's a Frankenstein of all 3 accents and I don't know what to go with.
Some points for both:
▪︎ American accent sounds "cooler"
▪︎ British accent sounds more "proper and elegant"
Australian accent sounds more "relaxed" (but I dislike this for myself, personally).
There's no one single British or American accent. Liverpool? Florida? Newcastle? Manchester? New York. Even within these places there's different accents.