Nice work. As far as upgrading I don't think there is a difference between the old and new as far as diodes or drivers go so the cost would sort of be a waste.
Amare technologies has some new panels out which should be on the web soon and now eBay sells pre wired top bin 3590 cobs with drivers and heatsyncs for 440$. Now either of those 2 would be a great upgrade. Watt for watt these 2 options will just about double your light for the same wall wattage. These eBay cobs are made to order and are tested for 24 hours before shipping. The Amare comes with a 5 year warranty and any issues in the first year he sends a new one immediately.