I’m always happy to improve, however I am conscious of my expertise. I’ve included a few default styles that work out of the box for people who prefer just that feature – it’s also what I run on my own sites. I know many users want custom CSS and build/enhance the styles. If they encounter problems, they come here to the forums and I help if I know how to.
But, in this case, I don’t know the answer to these questions without attempting to spend significant hours learning this level of CSS customisation. Hours I’m afraid I don’t have.
I completely understand if you feel the need to switch. There are quite a few other related posts plugins that have bigger teams behind them, particularly those who operate on a commercial basis.