Heat Holy Stone: Increase Cri by Percentage and Disable Opponent Physical Defend.
I recommend these two because most of players using Reduce Cri by Percentage and Value.
To increase your cri damage you have to use Increase Cri by Percentage.
Level5 holy stone should get 3.5%+ for Disable Physical Defend and 2.7%+ for Increase Cri Damage by percentage.
Cool Holy Stone: For PvP/PvE use Reduce Cri by Value and Reduce Cri by Percentage
If you have level 5 holy stone you should get 450+(by value) and 3.0%+ (by Percentage)