Late to this but I think it would be nice if PLD gained Oath from shield blocking while Sheltron/Intervention was in use. Now it may seem strange to have an Oath consuming ability regain Oath, but with Oath just being a pseudo recast, I like the idea as it gives some dynamic to resource/action. The more hits you/friendly receive while Sheltron/Intervention'd, the lower the recast of the next use.