Druid / Barbarian using tiger's grab + raging grappler --- Am I doing this right?

TL;DR
I initiate and release grapples multiple times during my turn to deal damage with "Raging Grappler" (barbarian rage power). Is this legal or am I doing something wrong?

I recently started playing pathfinder with my friends and came up with a build: Druid/Barbarian who shapeshifts into a dire tiger, charges with pounce and gets a ton of attacks with grab. These grabs are then turned into even more damage via Barbarian rage power Raging Grappler. And I'm trying to figure out what am I doing wrong, 'cause this is working WAY too well! Whatever I happen to pounce on is just obliterated instantly.

So, could somebody proof-read this? I think I might be doing my attack sequence wrong, so I'll start with that:

(pre-battle) Shapeshifted into a dire tiger

(My turn begins)

Start Raging
***free action***
Rage is active.

Charge
***full-round action***
Declare charge.
Move within reach.
I have pounce, so I get all my attacks.
All my attacks are at full BAB, so I get to choose what I use first.
I decide to do my attacks as follows:
- rake attacks (activated 'cause I pounce)
- bite w/ grab
- 2 regular claw attacks w/ grab

Rake Attacks
Nothing weird here, just roll to-hit and damage. (2d4 + modifiers)

Bite Attack
Do a normal attack. Damage done: (2d6 + modifiers)
It hit, so I get to grapple as a free action.

***free action***
No AoO 'cause grab says so.
Grapple check normally.
Check succeeds: I activate Raging Grappler.
Deal damage as if I had maintained it. (2d6 + modifiers)

***free action***
I end the grapple as a free action.

1st Claw Attack
Same sequence as with bite:
Normal attack. Damage done: (2d4 + modifiers)
Hit > grab free action.

***free action***
Try to grapple.
If successful, I do damage. (2d4 + modifiers)

***free action***
Let it go and end the grapple.

2nd Claw Attack
Copy paste 1st claw attack.

End of Turn
If the target is still standing and my grapple with the last attack was successful, I can choose to let go or let it be and try to maintain it normally on my next turn.

My thoughts
As you can see there's a ton of free actions and grapple checks. With these alone I'm effectively doing 8 hits after a charge. Is this how it's supposed to work? Please do tell me if something is wrong here.

Long post is long. Thank you for reading it!

It is the standard problem with making a grab attack, apply constrict damage, release, repeat. If you have a way to make multiple attacks it is pretty impressive.

That style of combat respect the rules as written. Maybe it was not intended (things like giant octopus become way more dangerous), but the only limit is the GM saying that you are making too many free actions.

It becomes worse with flurrying Behemoth hippo with Strong jaw.
4 attacks dealing 8d8+modifiers(=lots).
If you get to double that with raging grappler...
Then add haste to get even more attacks.
Yeah, I won't drop this on my GM or my druid is toast.

You don't get the rake attacks. To use Rake you have to BEGIN the turn grappling. You can't initiate a grapple and rake in the same turn

You don't get the rake attacks. To use Rake you have to BEGIN the turn grappling. You can't initiate a grapple and rake in the same turn

In this case Rake isn't related to the grapple. The pounce ability allows rake attacks.