Currently NIN & WAR cover all the Red Procs, so these jobs are a 100% must for Abyssea Tiered NM pops, or when you are after Atma. There are 18 other jobs in the game please make them more useful in this respect.
I spent a week leveling NIN & WAR after Abyssea came out(well after I got back into the game after Hero's was released). I am still a SAM at heart, and would much rather be able to full time this job than my two new twink jobs.
Consider one of the following:
1. Add more low tier elemental weapons kills that can trigger Red, (Ie Freezebite triggers for Ice, but not Blade: To. Cyclone for Wind but not Gust Slash or Aeolian Edge). Allow WS's that match the element a 20% chance to trigger, even if they are not the right one.
2. Allow more jobs access to Weapons but give them low rank. NIN gets Great Katana, but SAM can't use a normal Katana.
3. Have the weakness's be something that the claiming/popping alliance/party should have access too, assume everyone in the group has capped there weapon skills (If not that person should get on that). If there's no WAR/DRK/PLD in the party, Freezebite SHOULD not be the weakness. If there's no NIN Blade: Ei SHOULD not be the weakness. (Remember this is my third/last alternative, #1/#2 would be much better, and still provide a challenge, as this would make Proc'ing very easy).
Abyssea is a great new place, but right now it's WAR NIN MNK BRD BLM WHM BLU THF. That's 12 other jobs with nothing to do to but be excluded.
edit I forgot about BLU