I'm using Lawnchair because I wanted to change the default search engine in the search bar on the home screen. I might switch back to Pixel Launcher if they make it customizable.
I use Nova Launcher because I'm used to it and there's really nothing that still can replace it. There are plenty of similar launchers, but none that's as feature rich as Nova. People love to hate it because it has been acquired by an analytics company, but I have data disabled for Nova Launcher, so it can't really do anything. Even on other older phones that don't have the option to disable data for Nova Launcher, it hasn't sent a single KB of data in months. I don't think it's a problem.