A year ago, which AI persona(s) I played against in single-player games didn't seem to matter.

1. The AI didn't play very differently based on persona.
2. The persona bonuses never meaningfully impacted gameplay.

In my recent games, though, this seems to have changed.  

Persona bonuses now make a noticeable impact, and the AI personas seem to be playing more true to their traits.

Have the AI Personas recently been modified or improved in any way?