Need a second opinion on home brew grapple rule

[taski]

I'm just starting a third campaign for a group of players I've been DMing for for several years. In the last campaign i ran we stumbled across a rather annoying problem in regards to the grapple rule. I was consistently having a barbarian player grapple foes who were several size categories larger than she was. I talked with my players and we all decided that a medium creature immobilizing a gargantuan creature was a bit ridiculous. The trouble now is my group cant come to a consensus as to how many size categories above the players they can grapple effectively.

Also just to avoid confusion, anyone grappled by a larger foe can still make the normal CMB checks to gain control of the grapple, we're simply looking for an agreed upon size in which "gain control" is equivalent to "drop as free action".

[MacGurcules]

Well, the size limitation for most other maneuvers is one size larger, so Large size for most medium grapplers. For consistency, I suppose that's not a bad place to land.

That said, what's your main problem with grappling oversized creatures? Just that it breaks verisimilitude? If that's the case, might I suggest that you're simply not being imaginative enough? Grappling doesn't necessarily mean you have a creature completely at your mercy. It just means that you have it somewhat restrained and it needs to devote a some of its attention to you. It could involve pressure points, tangling up limbs, or just keeping an enemy pushed off balance. You might have that colossal dragon "grappled" because you're tugging on one of its legs hard enough in the wrong direction that it needs to spend some effort righting itself. You might have that cyclops "pinned" because you've got hold of his nosering and it's causing him so much pain he can't do anything else.

Grappling is one of the very few combat maneuvers that's worth specializing in, precisely because it doesn't have a size limit. In my opinion, forcing an upper bound just limits the options your players and NPCs have available.

[taski]

alright, my initial thought was to allow for grappling up to two size categories larger that way a medium creature can grapple a huge but not a gargantuan or colossal. similarly a tiny creature can grapple a small or medium but not a large or huge creature.

as to the creativity of grappling, that's kinda why my group was on my side with this one. I try to make every battle as cinematic as possible with my descriptions, i also try to let my players be creative in their attempts to overcome challenges. because of this, how i describe a situation might allow a player an advantage or disadvantage that wouldn't otherwise exist. the example of the cyclops being held by the nose ring is a good one until one of my players points out that it should no longer have reach in the squares behind it due to its positioning (we do use facing rules in my campaigns).

Im willing to put certain flair into the descriptions of breaking a grapple i.e. a character breaking a finger of a colossal creature holding it in order to escape the grapple. but it just seems a bit comical to imagine a 6ft person restricting the movement of something upwards of 40ft tall in any significant way.