It’s time to get into the gnarly topic of CSS cleanup. InDesign’s CSS is dreadful. There is no point pretending anything else. I would strongly suggest that bespoke CSS that is used for, say, your publishing house or a series of books would be well worth your time. In my work for a variety of different publishers and kinds of content, I almost always start from the InDesign CSS which goes some way to mimicking the print design. But I modify that CSS heavily - both for simplicity’s sake but also for complex reasons around accessibility.