It really depends on the campaign. IMC, FE Outsider(Evil) covers most outsiders that the PCs will ever meet -- Slaad are CE (IMHO and IMC), Fey cover the CN niche, and Modrons & Inevitables are of type Construct -- so there are not a whole lot of foes that fall under Outsider(Lawful) or Outsider(Chaotic).
Also IMC, the humanoid races are Human, Elf, Dwarf, Reptilian and Goblinoid. That's it. Not much game difference between that limited palette and FE (Humanoid).
Finally, I love templates! So PCs expect to see half-dragon trolls (type: Dragon), half-fiend bugbears (type: Outsider(Evil)), shadow tigers (type: Magical Beast), half-fiend shadow mineral spellstiched ancient dracoliches (type: TPK), etc.
So, IMC, this would have little or no effect.
Cheers, -- N