One is that I did a bit of poking into the state of Object Relational Mapping. The conclusion that I have come to (which is slightly odd for someone who has been working with OO concepts for more than 15 years) is that I want to focus on a relational design for the core star data. SQL is a mature and widely understood technology that is superior for exploring data than the object based approaches that I am familiar with. While maintenance and mapping apps will need object models, these might be best customized for purpose rather than aimed at generality.
The other is that, while a blog is a great place to discuss ideas in general, it is not a great tool for organizing and re-organizing design documents. I have two choices there: I could use standard word-based design documents, or I could set up a Wiki. Wiki interfaces are very good but are not the same bandwidth (at least for me) as a word processor. On the other hand, they do allow easy sharing of results, much as a blog does.