The current way to add and manipulate transitions on the timeline is a sort of "guess & check" method, you've got to have the right amount of handle frames before you add it, and the way it is displayed isn't very visually appealing.
I propose adding the same functionality that Audition has, where overlapping clips will automatically create a crossfade. This is an incredibly intuitive way of handling transitions, and can also be applied to Video transitions (as is done on other professional NLEs). See attached gif for an explanation of what I mean.
Currently, overlapping clips on the timeline will create a cut. For editors that use this functionality as a shortcut (no pun intended), this "auto crossfade" feature would be optional (easy to toggle on/off on-the-fly).
I think this would be a great way to increase productivity for transitions, as well as avoid accidentally losing your work by inadvertently overlapping clips when moving things around en masse on the timeline!