One benefit of Crossrail that I haven't seen mentioned often is that it will provide some desperate relief for the Piccadilly Line Heathrow Branch which suffers from some severe overcrowding, particularly during peak hours and is very busy throughout the day. I commute to Hounslow Central and the train are consistently very full on the Heathrow Branch. The problem of overcrowding is made worse by all the luggage from Heathrow passengers which blocks standing space. I have frequently seen passengers being left behind at Northfields and South Ealing Stations. The situation is also worse as I'm pretty sure during rush hour the 3 Northfields starters don't run, meaning the branch overall has a service reduction as those trains would normally be able to pick up and clear Northfields and South Ealing platforms of passengers. The Heathrow branch could desperately do with a frequency increase, which I know won't be possible until the Piccadilly Line upgrade. But otherwise hopefully Crossrail will take away the majority of Heathrow passengers from the Piccadilly line and provide some much needed relieft for commuters using the line.