As has been said The Hundred just isn't needed.
It was only put forward as a tournament because the BBC didn't have any live cricket to broadcast and wanted something of their own. Somehow it's been timetabled at the same time as the 50 over competition at a time when England's performances in 50 over games have taken a bit of a downturn.
If the ECB want a successful national side then they should invest more in those formats at county level.