Champions are not created equal.
Some are worth their weight in gold, like the spider riding, lightning bow shooting, 25% crit assassin with 3 death and 3 something else.
Some are amazing for their abilities, like the 30% unrest reducing, road building, population increasing governor.
Some have insane potential, like the assassin with the warrior damage perk, Earth magic, who pays his own wages.
And then you have level 5s with 1 trait and crappy gear, or level 9 with no real strength who need hundred of xpt to level.
It only makes sense that some of them will be VERY expensive, and some of them will be cheaper. But to have Karavox being able to recruit the likes of Thanalia on turn 1 is just silly. And then again, it is a single player game...