I have had the issue before of the logo being fuzzy or out of focus. The first thing you can try is hovering over the logo from within the editor and click/drag the highlighted corner to resize the logo. For whatever reason I've had success in having the editor think a moment about the resize and it appears to almost re-render the image, sometimes. This has not worked in all cases. If it comes down to it and you have no success with it I can show you a way with JavaScript to swap the source of the logo image to pull in something with a higher resolution. There are two sites I'm working on that have the same theme where the image would just not load in clear no matter what I changed. I have the images stored elsewhere (in my case on a remote server), but it may work just as well having the image stored in the Assets folder. There is a small snippet of JS that runs to swap the images and it is unobtrusive and does not affect load times. Despite being a minor annoyance in general it has worked okay for me and is a relatively small compromise for clarity.
