This is really neat! I've been thinking about ways to better stay in touch with friends and this might help. Right now it appears to be mostly about activity logging. I did see the "suggest" feature and I think that could be a point of expansion.
Simular to your own thinking, the "suggest" feature is why I built this in the first place, but sadly it has gotten the least amount of love because I had to first build the foundation so it would have friends to suggest in the first place.
If you have any suggestions (heh) for how to improve/expand upon this feature, I'm all ears!