Being given suggestions about how to be thoughtful further removes the 'thought' from the so called 'thoughtful' act. Though I haven't signed up, in technical terms I'm sure its a fair achievement for a weekend project, however I really think it misses the mark in an area where there could be much larger scale opportunity.
For example: you're limiting this service to romantic thoughtfulness, completely ignoring being thoughtful to people with whom your intended users might have a non-romantic relationship.
There are quite a few reminder / notification type projects popping up lately and I have to wonder how long-lived they will be even for avid users. I can't help but think its eventually going to feel like spam (even if your email content is fantastically insightful and useful).
With that said kudos for an interesting idea that you've made a reality.