I know you said SSH and not SFTP, but they're really the same thing. I use Cyberduck a lot, and if you SFTP to a server with it you basically have exactly what you're looking for: a GUI for SSH. There's no way to sudo with it however, as far as I'm aware, but I'm not aware of any GUI tool that lets you open files as root. There are very good reasons for keeping sudo a CLI tool.