Skip Excel Online
Allow Excel files to open in the desktop app in one-click, by default, without opening Excel Online. Absolutely hate Excel On-Line. It's very slow, lacks functionality and is a drain on efficiency.
You can set the site to default to open in the app instead of the browser. Also, each library can be set to open in the app or use the site default. Unfortunately, still have the slow Excel preview that shows up from the file menu.