Hi rice.shawn, great idea!
There's a preliminary packaged workflow for a similar workflow, with a few more features in it, hosted on github at: alfred-caffeine-controls
It seems to work okay, but I found I disliked a few things about it:
a. if I've got caffeine enabled already and give it a new time, it toggles it off
b. it only supports "on", "off" and "X" seconds, not hours
I've written fixes for both of these but haven't submitted a pull request for it yet. I'll aim to do that by the end of the week.