Optimize for what? Your own health, or the group's? Ebon is a team-oriented set, and Green Pact is more selfish.
If you also use Beekeeper, another purely health set, then you may run short of stamina for blocking, and want to consider sets that provide that.
Problem with this setup is it's greedy af, which is not really what is required of a tank. In this game, tanks are buffbots, which is why basically all the good tank sets help the team, not the tank. Ex. Alkosh is 100% pointless for a tank except the 5 piece, which buffs group damage. Ebon is worse than other sets (ex. PD) for the tank, but is a huge help in trials where dps are min-maxed; torugs is used only to increase the crusher debuff. There are situations where greedy is good (think last round of vDSA), but typically you shouldn't need this level of regen if you have a half decent healer.