I'll comment mainly on the Kraken, as Grapplers have a startlingly intense frontloading and fairly limited ability to gain advantage over monsters like the Kraken. Basically, after PsyWar 3/Totemist 2/Barbarian 1 (plus Practiced Manifester and Open Chakra (Arms)), you've gotten the vast majority of non-PRC Grapple output, and the PRCs are being
very harshly shamed by your +24 Strength, Gargantuan size, eight Improved Grab triggers, and
Natural Attack derived Constrict.
Looking over
a Grappling handbook, a Dragonborn Azurin Totem Rager Black Blood Cultist, one of the more extreme Grapple pushes in the game, caps at +63. With Rage, an assigned 18, a +5 Tome, and +6 belt, it has only 6 more strength than your base statblock, ends up with 5 less BAB, gets +8 from feats you have
zero complications taking, and +12 from a single Soulmeld.
A PC Kraken
with no items or class levels can readily compare to this rather heavily optimized and kitted out PC grappler, by assigning an 18 to Strength, getting Improved Grapple, then Shape Soulmeld (Girallon Arms) and acquiring 4 Essentia from Bonus Essentia and two +1 Essentia feats, for +60 to Grapple checks. And can make twice as many per round. If you let this thing have 9 levels or more,
it will defile the game with Black Blood Cultist 8 making every successful Grapple check set off
every Natural Attack you have. All 10-12 of them. Of which 6-8 instigate Grapple checks when used as attacks (depending on if the Claws overlap your Arms or not).
I suggest 12 RHD, giving access to 3rd-level PsyWar powers and Totem Rager 5's duration extension while making Black Blood Cultist 8 nearly squaring your damage potential be your entry to Epic, and agree with not giving it a direct negative level adjustment because Legendary Wrestler is a +10 and, as demonstrated above, it's actually a well above-curve Grappler with optimized PCs just by making it a PC, even if it gets to do
literally nothing but Grapple. Being that it's Gargantuan with eight limbs, this is a quite possible winning strategy as far as beatsticks go, even if your raw damage potential isn't as dumb as an Ubercharger.