You can set a date/time alarm for ToDos.
I don't think so. Under View menu, you can have uncompleted ToDos show on top of note list. You can view all your ToDo notes using search type:todo.
Sorting by uncompleted ToDos by due date would be useful. Perhaps that's something @JackGruber's Note Overview plugin can do. If so, then you could drop that overview note into the Favorites (plugin) panel for one-click access to uncompleted Todos sorted by due date.