It's one of the things I really would like to do, but pulling historical data (at scale) from the blockchain just doesn't seem viable without massive amounts of infrastructure. It may be possible once more API endpoints become available, but currently it's a bit rough.
I might look into mirroring the blockchain into a more traditional web database, but that's going to take some time. I also need some of this historic stuff for steempress, so it's moving from a want into a need rather fast.
Yeah i see, steempress also looks cool - will keep following your progress man