I have only played as Rome so far and I have yet to finish the campaign. It honestly was too easy I thought. I think I only lost one battle. I stopped playing it due to boredom and summer came along so my gaming usually is reduced anyway.
Last night I saw that Rome had a huge update so I did some reading on it and decided to give the grand campaign another go, this time as Iceni. A couple turns in I tried to take the town to the north and was soundly beaten. I think I lost due to a combination of not playing the game for a few months and being used to my Romans soldiers steam-rolling everything in their path.
So, I decided to start the Iceni campaign over again. This time I was a bit smarter and didn't attack right away
I built up my army a bit and also sent in my scout to poison the garrison, this time I was heading to the west first since they have gold. I was about to declare war when my neighbor to the south declared war on me. Well, that threw a wrench in my plans. I re-routed my army and scout down there and besieged their town. One turn later they paid me for peace. I then headed back to the west and now they have 2 armies...
That's about as far as I got last night but so far I am enjoying it more than the Roman campaign. I'm not sure how much of the difference is due to the patch and how much is just the different culture but is definitely more challenging.