We just switched over to New WF Experience and we love it. I got very excited to see a place to change "Planned Completion" at the top right of the project header. However, the deadline is hard set to midnight, which makes the entire function useless to us, since it defaults the final task date to the previous day. Changing that hard setting from midnight to 11:59 pm, or some other late-night setting, would make this function jive with the task dates, and that would be invaluable.
For example, I have a project whose Planned Completion is 8/1 and I want to change it to 8/30, I can go to "Planned Completion" and change that to 8/30 (which is super helpful not to have to enter the Edit screen, go to Overview and change it there). But since the new Planned Completion function defaults to 8/30 at midnight, the final task in my Tasks schedule changes to 8/29 instead of 8/30, and I have to go into Edit > Overview and change it to 11 pm anyway, which defeats the whole purpose.