This is such a simple concept. I like it a lot. I also love the fact that you've put in the effort to record all the sounds and voice lines. There is also an interesting story and a nice ending to the game. Nicely done!
Other things I like:
- Gameplay is simple to understand
Suggestions:
- As you said, the game would benefit hugely from randomising stuff like phone numbers and events
- Subtitles would be nice. The delivery guy's voice is hard to understand at times