Because having a lot of STR and INT will reduce your available stats points for things like VIT and DEX which can affect your chances to survive and limit the things you can do (imagine soloing Ifrit and he lands you a nice powered up Pulse Strike while having 1 VIT). Having 120 base STR doesn't sound bad if you have access to a pair of Megingjards but having 120 INT too will make you a glass cannon. Having 60~100 INT would be enough then have a somewhat high DEX, nice VIT, a bit of AGI for snapping and leftover points could go to LUK for additional damage.
I have yet to test those Sura Gloves but if you don't have access to Megingjards either then go for 100~110 STR and use one or two Vesper Core 01.
A Phen accessory is always required (alternative can be an Orlean's Gown of Wild Cat STR+3) as it makes your GFist casting uninterruptable. For a Phen Card the accessory of choice is the Diabolus Ring (SP+100 and +10% ATK against Satan Morroc).
Also, the moment you have the best of the best of the Sura equipment you'll be looking for new SP (both direct and percentage) increasing equipment as the ATK part will be already as high as puppy.
Edited by DamiaN468, 24 February 2014 - 04:15 AM.