Continuing on from the first post, I learned something very interesting from a colleague doing her own experimenting.
In addition to substituting an Image Web part for an Excel Web Access web part, you could also save an Excel file as a htm file, then after saving it in a suitable location on your SharePoint site, use a Page Viewer web part. It should look great.
I really like this because you can use all kinds of things not possible using a Excel Web Access web part. (Keep in mind any image is not going to be interactive though). For both image (jpg) and htm files, the rendering is a lot better, depending on the complexity of what you are showing.
I'm not done yet. No matter how good things look, somebody may want to print everything. I've noticed that trying to print from Internet Explorer is sometimes not possible because not everything will show (don't know about other browsers as I've not tried them for this)
A solution is to save the charts/ranges from Excel as a PDF file. PDF files can't be used in a Page Viewer web part, but you can upload them as a separate file, then link to them (preferably have some text above or below the Page Viewer web part, along the lines of "Click here to print"). Where I work, the file will open in Adobe which is just the right tool for printing PDF files.
Okay, next time I'll have some pics. Because I want to show you how easy it is for Excel to create HTML tables in SharePoint.