That's nice. Let's actually talk about where this feat is useful though because that is how the game works, you don't really care AT ALL about most of those things on a particular build.
So let's take a DC caster (it's a wizard because OW feat slots become more of an issue)...
- +1 DCs
- +3 Concentration
- +20 HP
- -1 Feat Slot
- Few more SP from higher base casting stat
- +1 to All Saves
Not so bad I agree. However, instead the same person could have done 2 Barb lives, 2 Wizard lives, and 2 FvS Lives. (They cut out monk, fighter, rogue, ranger, pali, cleric (this build does not care about that school) NOTE: they also could cut druid/artificer/bard for three less times around the treadmill). They would have the same hp bump, +6 Spell Pen (which is frankly more powerful), some SP bump from FvS. For that they lost no feat slot so they can throw a feat into the Focus they actually care about (it's usually necro/enchant with one so high it is irrelevant in most cases). They also saved two more feat slots for spell pen feats and 6 AP. The second build is actually alot better off then the first one.
Every incentive is about what could be done instead. In this case, well a player could just plain get more effective PL for their build.
Let's take another build now...we will say fighter (because a pali, rogue, barb...they all are so tight on feats that the slot is a major sacrifice)...
- +20 HP
- +1 to hit
- +1 tactic DCs
- +1 damage
- +1 to all saves
Not bad at all, but those skills yeah the fighter could care less...maybe intim IF they are a tank build. So instead of leveling up an artificer, ranger, druid, cleric, bard, FvS, wizard, sorc they go 2 barb, 2 fighter, 2 monk, 1 Rogue more for equal lives. You will note that the past lives grant almost nothing for the a melee fighter that are given up. They end up with the same HP, +2 to hit, +2 tactics DC, +2 damage, +1 sneak attack damage, one more feat slot, and one less to saves (luck of heroes if they really wanted for equal).
Jeez, that second one is a complete no brainer.