STR-INT...Two person party do i need Dex at all?

[Arcell]

The only thing PGL/MNK would use Dexterity for is accuracy and evasion. It's not worth pumping the Dex stat itself though as there's gear out there with evasion and accuracy bonuses that would actually help far more.

[Soukyuu]

If you feel you are missing too much, just grab some accuracy rings. They come every 10 levels starting with lv7 and are usually enough to not miss all the time.