Having "hard" factions is entirely a good thing IMO. That way it allows a player to progress through the game and encourages replayability.

Having said that I didnt find either Saba or Sauromatae to be particularly difficult. Saba you get all the time in the world to subdue arabia, and finances are pretty strong. The hard part is that beating the ptolies on the battlefield requires different tactics to most factions as they have no "obvious" way to kill phalanxes. Also they do tend to suffer high casualties so invading far from your homeland without access to reinforcements isnt straightforward. But overall you have a secure and easily defendable position, its just expansion thats tricky.

With the sauros, the money part is tough, but using horse archers and one FM its easy as hell to win almost every battle with extremely low casualties. Taking on the other nomads is a little tougher though.

I suspect many people might put Pontus in the tough category also. But certainly no-one needs a "fix" IMO.