I absolutely loved the mechanics and fluff behind Incarnum. That being said, I never really used it because the four classes didn't balance out against 3.5e classes.
Almost all of the meldshaping works out to "you don't have to pay for a buffing magic item." That's great, neat, awesome but... wait... I have to give up all the other class abilities I'd normally get? For instance one class is almost the same as a paladin, only it doesn't get any important abilities. It gets melds. Well, sure, +5 to Sense Motive and Climb might be fun, and the ability to shift a few points of essentia around at will to get maybe a +2 natural armor bonus sounds fun too, but... I wanna smite evil.
So, despite really liking Incarnum, I'd have to say that to fit Pathfinder's rules the classes (and meld list) need a serious revisit. The classes need verbs. They need to be able to DO something, beyond HAVING something. You could probably take a PF paladin, take away the spell-casting and give it some meldshaping. That'd be fair. Take a sorcerer, give it Incarnum bloodline and it gets some melds instead of the other stuff. That'd be fair. A fighter without the extra stuff that isn't feats... give it a few melds. Fair. And so on. Leave the active abilities classes get such as smiting, spell-casting, and feat choices respectively. Fair, and probably fun.
I wanted to see melds that did things like "you succeed at a melee touch attack and inflict one point of Dex damage per point of essentia you have invested in your Adder's Venom Gauntlets." Oooooh. Or "your Salamander Skin Gloves add 1d6 points of fire damage per point of invested essentia to the weapons you wield while wearing them." Basically, MoI was (mostly) missing melds that actively impacted anyone other than the meldshaper. Well, um, buffs are awesome and all, but who'd play a monk that doesn't get flurry of blows or ki points or fast movement or AC bonuses but it can cast bull's strength and cat's grace on itself at will? Um. Yeah, whatever.
Any Magic of Incarnum conversions for Pathfinder? How does the base classes stand up to PF classes? Do they need a major overhaul or can they be played close to as is?
Exo
On their own, Incarnum base classes are weaker then PF base classes, i will have to say. They would definitely benefit from a small overhaul.
I will say however that the Totemist was the best of the three, and pretty darn cool.
I have been using Incarnum in my PF converted Savage Tide Campaign. I made it something the Ancient Olmans used and can still be found on the Isle of Dread, so the players are completely unfamiliar with what to expect when it comes to "wierd native magic stuff" Mummys with claws that cause bleeding damage, or fatiguing roars that batter the opponents with sound like a gale? they didn't think they were mummys let me tell you ;) Gargoyle who could breath lighting like a behir? also a nice surprise.
Necrocarnum effects for the melds and undead combined with creepy visuals help me cultivate the atmosphere the players are delving into a forgotten world with secrets of its own. The totemist meldings also give me another excuse to have the native carvings have appearances of man/animal hybrid looks.
My PF use is mostly a homebrewed overhaul, but i find it workable enough. There's a lot of flavor in that book to tap if you are willing to put in a little work.
I would agree whole heartedly with Rathendar the flavor and uniqueness are excellent just needs a bit of an overhaul and prolly a bit of upping the power to make it PF solid.
Loved that book so i wish you the best of luck with any conversion/ upscaling you or other do.
Funny, I was going to post this very same question today, and then I saw someone beat me to it!
I run a homebrew PF campaign, and the PCs are about to enter a completely new realm. I wanted to add something interesting and different to it, and Incarnum was the first thing I thought of. Like Anguish posted above, there needs to be things other than buffs for the classes. Does anyone know of any fan created Incarnum material?