I noticed that Berlin is unsatisfied with the current implementation of rebirth passives, so I thought I'd suggest a different method. With this method, there would be a second page of the skill tree devoted to these passives.
After your first rebirth, you would unlock the first tier and be given one point. The first tier would consist of the current first rebirth passives or entirely new ones if you feel like making them. The second and third tiers would work the same way.
This would add more customization by letting the player choose to forego a second or third tier passive in order to grab more lower tier passives if they so desire. It would also allow players more freedom in their leveling process (I.E. they wouldn't have to play as a certain clan just to grab their passive).
It would of course be up to you whether to allow players to respec this page of the skill tree, but I think it would be a good idea.