> And wouldn't it be better to learn words such as places and names gradually over time as I stumble upon them rather than learning how to pronounce a lot of characters in a language I don't like?
That's a good plan.
> Mandarin sounds quite bad compared to Cantonese for me, and I don't want to develop a habit of speaking Mandarin instead of Cantonese for many occasions.
You are well informed. Mandarin pronunciation relies a lot on "rolled tongue" (捲舌). Once you develop this habit, you'll have a hard time switching back to Cantonese because Cantonese hardly uses rolled tongue at all.
That's a good plan.
> Mandarin sounds quite bad compared to Cantonese for me, and I don't want to develop a habit of speaking Mandarin instead of Cantonese for many occasions.
You are well informed. Mandarin pronunciation relies a lot on "rolled tongue" (捲舌). Once you develop this habit, you'll have a hard time switching back to Cantonese because Cantonese hardly uses rolled tongue at all.