Not a whole lot of constructive criticism in this thread. Mostly pretty vague. I do agree that Tame is overpowered as is. Tame needs to be nerfed. And Wealthy (again).
Another thing that would make the game harder is putting a cap on how many Pioneers each AI player can have at any given time. Make the cap 4 or 5. In my last game that I played on Insane (started on 1.1), late game, every AI city was surrounded by armies of Pioneers. I thought that was supposed to be fixed already. The AI players have plenty of money, so I can't think they're doing it to save on wages. I was able to level up several champions just killing Pioneers. They even send them into my territory en masse, like "Here, have some free XP." Maybe if the AI players built more combat units, they'd have a better chance.
Reasons Tame is overpowered:
1. You can get bears, who Maul, and Maul is overpowered, especially when you have Lucky and Commander bonuses.
2. You get wageless units. Lots of them. For not much mana cost.
3. Acquiring many of these wageless units inflates your power level significantly, which makes other factions that could probably trounce you not want to attack you. Even though I was playing on Insane, nobody declared war on me until I started declaring war on people.
4. You still get the XP for the win. I honestly don't disagree with this, but with all the other stuff, it is a contributor to Tame's power.
How can Tame be fixed? (several options, but don't implement all of them):
1. Increase the mana cost and add a casting time of 1. Adding the casting time prevents getting extremely powerful creatures (like the Hoarder Spider) early on.
2. It wouldn't make sense to pay bears and spiders, but maybe put a mana maintenance on the creatures you tame.
3. I think this has been partially fixed already in 1.2, with the change to how power levels are determined. I haven't started a new game on 1.2 yet to find out.
4. Reduced XP for taming beasts. Or at least don't give XP to the tamed beast.
5. Change it so it can only be cast once per combat. Even with a 10 turn cooldown, I can tame all the beasts in any army. It's a boring process, but I can do it.