1)
http://www.ffxiah.com/forum/topic/20485/atma-choices/ : Hasn't changed much, but DD has gotten a little better.
2) Without magian trials, Phurba / Twilight Knife. If you can't get one of them, main-hand Mantodea or Angr Harpe of your choice and offhand the other.
3) Without Twashtar, DA Parazonium mainhand / STR Kila offhand is a pretty good combo. STR Kila x2 might be better on harder content, though. Inside Abyssea, STP Fusetto is a very competitive. STR Kila is a good offhand for Twashtar as well, but DA Parazonium falls off a bit. AGI Kilas are your utility-knife. Get one at least, two if you're dedicated. They're a very efficient location to trade DD stats for evasion.