RSVP default end time

I can't find anywhere to change the auto-populated end time in an RSVP date field. Currently it's 30 minutes, but 99% of what I do is 1 hour, so having to change it every single time is driving me crazy.

Also, having to type in the times is annoying. The date has a great popup that lets me just select the date, we need something like that for the time.

Not sure if this falls into its own feature request, but a way to pull up a calendar and select the date/time would be phenomenal!