Inner Circle
I believe those three are all excellent candidates. The final decision lies, of course, with our Lord but I think any one or even more of those candidates would be of benefit to the Inner Circle.
I am in two minds in regards to placing any of the Outer Circle with new memebrs of the Inner Circle immediately. On one hand, it smacks of a lack of confidence in them not to but on the other hand, I am of a mind to allow them time to make the adjustment to their new position first before giving them added responsibility.
But irrespective of that we certainly do need to place Caracatus' mentees with new Inner Circle members.