Some features are useful, while others are more for safety and convenience. One example of either is motion detectors which will shut the door if something (or someone) gets too close to it.
Another feature that goes with that one is safety sensors on the opener itself rather than just the remote controller. Safety sensors detect things like cars, pets, children, or anything else that can get in harm's way by preventing an accident from ever happening.
Other features include wall-mounted control panels instead of hand held remotes so as to avoid dropping them when trying to operate the garage door opener. Another handy item would be keyless entry so people do not have to worry about having a house key with them at all times because they have their garage door opener remote.