Synergy > individual power
TONS of people have Orlando's up the majority of the time, chaining w/ him is very easy, chaining is a huge change in damage. 2 Orlando's will greatly out damage 1 Orlando and any magic caster.
Also, best to focus on just 1 character at a time. you can look up the damage formulas, but your attack is basically squared, so the higher the better. and 1 high value will result in much more damage than 2 lower values.
If you don't have Warrior or Light, then focus on Cecil for your tank. Refia is a great healer. Cecil and Refia can but make use of a dual cast, so work on that for TMR if you can. Though getting Gilg's TRM for Orlando is more important.
Outside of that, you may have a green mage and/or buffer/debuffer that you can level up as well.