The funny part about respec issues, is that using the one from toybox apparently does not cause the Mythic Path trigger issues, compared to using the ingame respec.
Full respec also allows some feats that are indirectly unlocked to serve as proper requirements for other feats. I.e. you cannot choose Shatter Defenses when leveling up regularly, even if you have the Hex that grants Dazzling Display. But if you respec and pick the levels all at once, it does work. Dazzling Display still stops working after a reset/reload, but Shatter Defenses stays usable.
It's sad that the Demon Path main mechanics are so underwhelming, because the Demonic Charge is really fucking good. Even at Rank 3 its already 6d6 unholy damage in an aoe, usable every turn, as a move action. Has the same issues as regular abilities that count as move actions though, as in you need to cast it as your last action, or it will keep you from getting a standard action in at all.
Part of me wants to cheat high saves to see if there is another solution to Insistent Summons if you repeatedly pass the saves, or if its inevitable that Hepzamirah will overcome your willpower/rage and summon you to the Abyss.