Only a minor inconvenience/annoyance for me, but custom padding would be particularly handy for TVE recordings where the programs run 1-2 minutes behind the actual guide's stated time due to streaming lag. I always seem to get an extra minute or two of the previous program at the start of the recording, so in this case a start delay of 1 minute would be ideal.
At the end of the recording, the only padding options are 1 and 3 minutes. If I select 1 minute, sometimes the end of the program is cut off, but 3 minutes is too much. Here, I think 2 minutes padding would be a good catch-all for TVE.