Arborint and I are going to be working on a lightweight ORM in the same vein as our Pagination classes. Basically, we want to write something that will fill the void between a Table Data Gateway/Active Record implementation and heavy duty ORMs like Doctrine or Propel. Ideally it would be a layered solution, possibly even built over Skeleton's existing TDG or AR classes. We are using Fowler's ORM patterns as a starting point, but may go in a couple of different directions depending on where the code takes us.

I was wondering if anyone had any suggestions as to what they would like to see in a lightweight ORM. Any input would be very much appreciated.