Playing with grapple rules

An interesting character build quirk popped up while I was making this monk.  What are the ethics of delaying a feat choice for one or multiple levels to satisfy prerequisites?  In the middle of a campaign, the rewards are somewhat mitigated by the costs of having to play down an effective feat for X levels, but during character creation you can handwaive away that inconvenience.  4th edition allowed feat retraining to avoid this complication entirely, but Pathfinder still plays by the 3.5 rules.

As a DM I'm not sure I'd allow, say, a new 12th level character to come in with all his feats selected AT 12th level.  As a player it remains an alluring option, especially here with a wealth of good feats being available at BAB +6, which only occurs for monks at level 8.  For the sake of testing out maneuver builds I'll go with a limited feat-delay strategy, but only two of twelve.

Str: 23 (17 +2 human +2 levels +2 item) (13)
Dex: 16 (14 +2 item) (5)
Con: 12 (2)
Int: 10
Wis: 16 (14 +2 item) (5)
Cha: 10

Class: Monk 9 (Maneuver Master)
HP: 9d8 + 9
SP: 36

 

Feats: 14 (5 level + 1 human + 3 E6 + 3 monk + improved unarmed strike + stunning fist)
H1: Combat Reflexes (up to 4 opportunity attacks per round)
L1: Stunning Pin (Stunning Fist as swift action after pinning foe)
M1: Improved Unarmed Strike
M1: Stunning Fist (DC 17 fort on melee hit, make enemy stunned, fatigued, or sickened)
M1: Improved Grapple (+2 grapple CM, no AoO)
M2: Improved Trip (+2 trip CM, no AoO)
L3: Dodge (+1 dodge AC)
L5: Snake Style (+2 SM, use SM check as immediate action to replace AC for one attack)
M6: Greater Trip (+2 trip CMB, tripped enemy provokes AoOs)
E6: Mobility (+4 dodge AC against AoO from movement)
E6: Snake Sidewind (+4 CMD trip, use SM check to confirm criticals, 5 foot step as immediate action after crit)
E6: Snake Fang (delayed to 9) (AoO against enemy that misses attack against you, if AoO hits spend immediate action to make another attack)
L7: Greater Grapple (delayed to 8) (+2 grapple CMB, maintaining grapple is move-action)
L9: Rapid Grappler (after maintaining grapple, may take swift action to make another grapple maneuver check)

Class features:
-Bonus monk/wisdom AC
-Flurry of Maneuvers: Make 2 extra combat maneuver actions of any type during full round attack action, at -2 and -5.
-Maneuver defense: Make AoO against foe making trip/grapple actions regardless of improved feats
-Reliable maneuver: Spend swift action, spend 1 ki point, roll twice for next maneuver
-Meditative maneuver: Spend swift action, add +3 to next maneuver roll
-Movement: 60'
-Improved Evasion
-Ki pool: 7 (swift action to use)
-High jump (+9 jump checks, swift action to spend ki point for +20 on acrobatics)


Gear: (46000)
Amulet of Mighty Fists (fire) [5000]
Bracers of Armor +3 [9000]
Belt of Physical Might +2 [10000]
Amulet of Natural Armor +1 [2000]
Ring of Protection +1 [2000]
Headband of Inspired Wisdom +2 [4000]
Monk's Robe [13000]
Cloak of Resistance +1 [1000]

CMB:  9 base + 6 str = 15 (+4 on grapple and trip)
CMD: 19 base + 6 str + 3 dex +1 deflection +1 dodge +3 monk +3 monk-wis = 36 (38 vs grapple, 42 vs trip)
AC: 10 + 3 dex + 1 deflection + 1 dodge + 3 monk + 3 wisdom + 3 armor +1 nat = 25
Sense motive check: +17 = 9 ranks + 3 class + 3 wis +2 snake

Hit: +12/+7 = 6 BAB + 6 str
Dam: 2d6 base + 6 str +1d6 fire

Example combat round, assuming Snake Style has already been activated:

Round 1:

1. 5 foot step to nearest enemy, full attack flurry:
2. Trip attack at +17 (+19 - 2) or more (assume hits)
3. Trip provokes AoO at +12 (defender has -4 AC from prone)
4. Melee attack +12
5. Melee attack +7
6. Grapple check at +14 (+19 - 5) (defender has -4 CMD from prone) (assume success)
7. Opponent attempts to and fails to break grapple on his turn.  +5 circumstance bonus on future grapple maneuver checks. 

Round 2:

1. Move action: Maintain grapple at +24 (defender has -4 AC/CMD from prone and  -4 dex from grappled condition).  Force enemy into pinned status.  (no dex bonus and -4 AC/CMD) [assume pinned replaces prone]
2. Swift action trigger: Damage maneuver +24, 3d6+6 damage
3. Standard action: Damage maneuver +24, 3d6+6 damage

OR

1. Move action: Maintain grapple at +24 (defender has -4 AC/CMD from prone and  -4 dex from grappled condition).  Force enemy into pinned status.  (no dex bonus and -4 AC/CMD)
2. Swift action trigger: Tie up maneuver check at +24 (helpless: dex set to 0 [-5], all attacks at +4 [functionally the same as the -4 AC/CMD, surprised Pathfinder hasn't fixed this quirk])
3. Standard: Enjoy a refreshing beverage as you wait for next round to coup de grace, or Damage check (auto-success) 3d6+6, or retry the tie-up.

OR

1. Move action: Maintain grapple at +24 (defender has -4 AC/CMD from prone and  -4 dex from grappled condition).  Force enemy into pinned status.  (no dex bonus and -4 AC/CMD)
2. Swift action trigger: Stunning Fist +12, 3d6+6 and DC 17 fort save
3. Standard: Damage or tie-up.

This build relies on getting AoO and swift action triggers for bonus actions, which can then be used on maneuvers (instead of normal attacks) for a better bonus and the opportunity to trigger even more actions.  It can actually get somewhat complex.  For example:

-Walk past enemy
-Enemy attacks vs 29 AC.  If miss:
-Miss triggers AoO (Snake Fang).  Use trip.
-Trip triggers AoO (Greater Trip).  Attack at +4.
-Trip attack triggers another AoO as immediate action from Snake Fang resolution.  Attack at +4.

That's basically three actions (two normal attacks and a maneuver) on someone else's turn.  And then you get to your own flurry of grapples and punches on your own turn, including at least one more AoO opportunity and perhaps four, depending on whether a new round comes along.  There's also some nice emergency defense by using a sense motive check as your AC once a round, which offers a range (with traits) somewhere between 19-38, which can apply to touch AC.  Other fun combos:

-Enemy tries to trip you
-Trip maneuver Provokes AoO (Maneuver defense)
-Use trip back at enemy
-Your trip provokes AoO (Greater Trip)
-Make attack +4
-Enemy's trip resolves (at 3d6+6 penalty if your second AoO hit)
-It probably misses, triggering AoO attack +4 (Snake Fang)
-Snake Fang hit triggers another AoO attack +4 as immediate action

That's four opportunity attacks (3 melee attacks and 1 trip) on an enemy's turn, and I'm pretty sure this is legit since each trigger is different.
1) Incoming trip maneuver
2) Enemy falling prone
3) Missed incoming attack
4) Snake Fang initial hit

You run into trouble when you start blowing immediate actions off-turn, since that means you don't get your swift action again until effectively two turns later, but you still have enough bonus actions on-turn to get your grapple on.  Or you can just opt to not make the second Snake Fang attack, leaving you the immediate/swift for Rapid Grappler or a Snake Style defense.

This monk's defensive qualities are still very wanting, however.  That AC is awful, and there's not quite enough money to blow it on more deflection/armor/natural.  Your AC also goes down when you're grappling (maybe Body Shield makes sense later, but that's another immediate action sink) so you'll probably get torn apart by other melee enemies.  You also probably cannot reliably grapple large supernatural creatures who probably have CMDs in the high 30s, meaning you'd need a 18-20 to initiate anything.  And forget effectiveness against huge creatures.

Would benefit greatly from Enlarge Person buffs.  Stunning Pin might not make sense since it eats a swift action, and that might be better served just doing damage within a grapple.  Not sure what that could best be replaced with.  There's no weapon focus for unarmed attacks, and no other ways to boost CMB.

It would, however, ve a very tactically interesting character to play.  At least until we start fighting dragons.