I've got on that train a few times and it is always empty. It's a good idea to run a train direct from the West as there are a lot of people getting on the train from Worthing/Shoreham and it would definitly help ease the ques at Brighton.
The biggest problem for the Eastbound platform is there are people waiting for different trains. They should just run trains Lewes-Brighton and then people can change at Lewes for either the Seaford or Eastbourne lines. It works on the Brighton side where people just get on the first train they...