Alright, I got around to beating the crap outta Lost Babil (and watched a few Youtube vids along the way). Here's a synopsis:
Constructing the team:
Party 1: Palom's Angels (Palom, Ursula, Porom, Luca, Leonora) [2-3 formation]
Goal: Pound the living crap out of the torso and/or hand with Petal Whirlwind
This portion of the monster likes fire (Thermal Rays) and ice (Freezing Winds) with a little gradual petrify.
Protect Rings and stuff from the Dragon armor series helps here. Ribbons or at least some Aegis Shields would work just as well. Other useful armor include the Cat Ear Hood and Red Cap/Jacket.
Since both monster spells have a very LOW spell power, surviving gradual petrification is easier (it's like Barbariccia, except just dumb). Not difficult.
Using Petal Whirlwind was great... in fact since Ursula was equipped with the Dragon Claw AND Godhand (both Holy elemental)... the attack did 50% more damage to the torso.. the hand didn't get the bonus damage. Apparently, the torso is vs Holy... so it makes a lot of sense to give Ursula elemental claws with Petal Whirlwind to deal exceptional damage (probably a great idea for the final bonus actually).
Blink is annoying, but easy to remove since the back row is a bunch of mages...
Party 2: Team Ninja (Zangetsu, Izayoi, Gekkou, Edge, Tsukinowa) [3-2 formation]
Goal: Pounding the living crap out of the head...
The character in the middle needs to be the damage absorber, as it seems to be targeted the most with Holy, Flare, and whatnot (occasional Firaga). Gekkou is great for this.
The chest seems to like to use Curaja, only rarely... and the hand is easy to quiet down. The problem is that you suffer from having to do long range targeting to the head...
The monster summoning is kinda meh... as Edge with the Rising Sun is more than capable of killing it from the back row. It takes a while before the monster summons the monster for bestiary purposes.
Healing is primarily through Izayoi, and Edge as the primary backup (Tsukinowa is the worst of the healers).
It helps to put the hand to "sleep" as it tries to annoy with with Firaga and some hits...
The best band to use was Wheel of Elements.. which I didn't expect it to be effective, but it really is. 15MP per character is worth it...
It may be difficult to get the armor for all the ninjas - you need to obtain some Pink Armors (at least 2) for Ursula since the armors she uses (Red Jacket and Brave Suit) are ninja compatible. Fire Scarf and Ninja Garb solve only two characters... so the second Pink Armor would go to Izayoi.
Bile and Bad Breath is part of the lame repitoire of the Malboro... but easily fixable with Rune Armlets and other stuff that blocks ANY of its statuses (Blind, Silence, Toad, Mini, Pig, Confuse).
Party 2 should primarily be designed to target from long distance... whether by bands, magic, or attacks (special or not).
Party 3: Team Baron with Rydia, minus Cid (Ceodore, Rosa, Cecil, Rydia, Kain)
Goal: Trinity Crusade to vs the CPU, Thunder Wave the rest
The difficulty here is trying to fit armor and equipment that is shared between Cecil, Kain, and Ceodore (and to Luca to a smaller extent). The Ultima Weapon, Ragnarok, and Holy Lance can be juggled a bit (Excalibur is the last resort with the Wyvern Lances as alternatives). Lunar equipment are only shared between Cecil+Ceodore... and Kain's best set would include portion of the Crystal armor set (with from Dragon armor that you can keep around).
I don't think there are any status effects to worry about... you simply have to be able to make sure you heal the character hit by the lame beam attack that deals 1/2 Max HP damage plus Sap... which should be easily solvable with Ceodore as the extra healer in the group.
It helps to lead off with Effect Form and then Thunder Wave... Ceodore and Rosa can cast Haste on Ceodore and Rydia on the next turn easily. Trinity Crusade is the goal... unlike the other parts of the Giant of Babil... this part is wicked easy.
Characters not chosen/considered:
Golbez - shares too much with Cecil, Kain, and Ceodore... could be difficult to set up, but the Enhancement Sword and his Ebony Robe should be enough to worry about.
Cid - too slow... Luca and Gekkou are better for what you need them for
Yang - kinda slow... you'd have to have a King's Band setup to make him reasonably useful (his Slow band with Ursula is semi useful as you need to hit multiple targets with them), he shares too much stuff with Ursula
Calca and Brena - it's worth considering ONLY if you get their best equipment.... they are most useful in part 1 of the battle and you could get away with using Luca and these two for Go! Calcabrena!
Edward - despite having a nifty weapon in Loki's Lute, it's useless for this battle (it's the weakest standalone weapon compared to the Artemis Bow and Arrow at this point)... he'd be great for healing, but not much else
Harley - useless w/o Edward, and even then you would be limited to her pathetic attack/skills and limited healing bands (you don't design your teams for Weapon in Progress or the special whip attacks)... at best the Feast of the Land band would be useful for the 1st part of the battle (and you could skip on her power by making her waste a turn vs Blink).
I had some time today to consider one potential team... this only sound good on paper:
Cecil, Golbez, Zangetsu, Tsuiknowa (and Ceodore)
You have two bands that can haste the party and slow down the enemy party. Adding Ceodore would allow for the Advanced Blade band and you can easily keep Zangetsu (Human Kite) and Tsuiknowa (boomerang) in the back. You could also put Golbez in the back since he can use magic, but he's better up front for regular fights...
I also like this party that I was testing with...
Luca, Calca, Brena, Palom, Leonora
This allows me to use the nice low cost Go! Calcabrena! band and use Ice Crush... good times. Helps to have Luca with the Limit Ring for this.
We have EVEN MORE themes now, but some old ones are gone...