The 1 block diff regeneration really is working very well and should scale up with growth easily due to the strenghts of the LWMA.

We are currently finishing up the implementation details and specifications of the susucoin blockchain text archiving system, codenamed SUMO. After SUMO is ready, we will be forking susucoin to a 512 byte OPT_RETURN to accommodate the extended functionality provided by SUMO.
Susucoin's official blockchain explorer is coming soon too.