Usually what I end up doing is junctioning Ultima to my Elem-DEF-Jx4, and Confusion/Break/Death to Stat-DEF-Jx4 and the rest go to Evasion-J, Str-J, and Luck-J. Not to mention Pain and Zombie and Slow are junctioned to my Status Attacks, so only Hex Dragons and Malboros are immune to these usually.
Pretty much nothing except for Omega is a threat to me right now.
Then I just abuse Demi/Bio/Flare + Triple on anything I come across and Devour anything that gives me good stats (see my earlier posts for my strategy).
This game is considerably easier to manage once you master Triple Triad and know how to manage your cards and item drops and how to refine them in to useful items and Magic for Junctioning.
It just takes a verrrry long time to get stable, yet powerful stats at Level 100 (since relying on Junctions is risky against Ultimecia who can blow your junctions out of the water). Right now for me the hardest stat to boost is MAG, simply because eating Behemoths isn't a perfect process, as they will either die by accident before they're weak enough to be eaten, or they aren't the easiest monster to get a random encounter out of around Tears' Point or the Castle (since I already beat the Deep Sea Research Center).