30% Health,
Upgrade 2 buildings at the same time
+3 Energy Regen
The order i would put in level of importance. While i would love to have upgrade 2 buildings at once...the reality is that only increases my IPH and improves my buildings...Doesnt really do much for me in the long run. (*well i can improve my defense buildings too...but lets be honest here)
+3 Energy is nice but gree just keeps upping the energy required. You still have to spend lots of gold to complete so while it is helpful i would take a 30% health regen first.