Eureka isn't that bad, had some fun today

[Avenger]

the only problem i see with it is there is almost zero reason to do anything but NM zerg train

For me at least it seemed that trying to get kill credit/XP/crystals at the level-appropriate NM spawn point was better than mindlessly killing everything. I also liked that some of the FATEs devolved into horrible bloodbaths like Odin in ARR before people figured him out.

It also seems more effective to split into multiple teams working on multiple pops simultaneously, since there is a point of diminishing returns and also since lower-level players don't contribute much to high-level farms.

But this is right I think - regular enemies don't drop anything and don't give a lot of XP or protean/anemos crystals, so there isn't a huge incentive to kill them individually as a party.