Taper features can be very useful, but are a bit difficult to create and use. A few improvements could help.
First, the text in the Taper dialog should say "Keep as Feature" instead of just "Keep as Feat"-there is plenty of room.
Second, it should be possible to modify a taper feature by right-clicking on it in the Structure Browser, or by pre-selecting a face in the taper feature and having modify and remove options on a mini-toolbar (similar to what can be done with faceset features).
There should be two "remove taper feature" options: one to remove the feature definition (and keep the geometry), the other to untaper the faces and then remove the feature definition (similar to custom features).
And, in addition to being to modify or remove a taper feature, there should be a command to "suppress" the taper (which you can do now by unchecking the box in front of the draft angle).