Creating Eidolon(s) for supported archetypes

Two of the supported Druid archetypes (Elemental Ally and Planar Extremist, or Summoner Broodmaster for that matter) don't allow creating Eidolons like a Summoner does, and creating a Follower of the Eidolon type doesn't really lead anywhere because you can't apply types, subtypes or evolution points.

Druid Planar Extremist only requires one Eidolon, but both Druid Elemental Ally and even Summoner Broodmaster require multiple Eidolons, which isn't even a feature as far as I know.

If there's any hotfix I can do, please let me know, and thanks in advance – keep up the good work!