Mission file downloads are slow. Many servers these days run moderately big mission files (60MB+) and are nearing the limit of what is reasonable currently. Some servers even encourage their users to download 3rd party applications to download the mission files faster to work around the currently outdated mission file downloading system.
So perhaps the mission file downloading could be looked at to make it at least a tiny bit faster? Currently mission file downloads are slow regardless of how fast your connection is.