England just need to start again with the entire limited overs set up, Australia were total shit only 2 years ago in the ICC champions trophy so it can change quickly.
4 years till a home world cup so firstly a coach with an actual track record in limited overs cricket needs to be appointed. Anyone who isn't fit for one day cricket or won't be around in 4 years needs to go so no more Broad, Anderson, Bell after this tournament. England need to pick a young side of players suited for the format and stick with it, no more picking no hopers like Harry Gurney. Gameplans need to be entirely scrapped, England try to make things far too pre-planned instead of playing the situation, there was no reason for the 10th-35th overs slow up yesterday on a good pitch, yes you want to keep wickets but its quite clear the team targets scores and are often happy to significantly slow the scoring rate as a result. Morgan needs to go as captain, far too negative, limited overs cricket is not a place for negative captaincy and yet instead of pushing for desperately needed wickets Morgan was happy to see Sri Lanka cruise along as long as they weren't getting too many boundaries.
And finally, but probably most importantly England need to only pick players who are a) comfortable scoring from the moment they come in, far too many of this side need to play themselves in so any wicket sends England to test match batting and b) comfortable scoring a run a ball, again far many of this side are happy to play out dot balls particulary in the middle overs. This is never more obvious than against any kind of spinner. The bowling is complete shit however and i'm not even sure who they can look too to rectify that. There's no particularly good bowlers in the one day game at the moment who are obvious candidates anyway.