The KH is probably the best for migration campaigns. You could migrate to a number of different cites. Sinope, the two Crimean cities, Kyrene, Massilia and those two Iberian cities, Syracuse, Krete, etc.
The only other faction I've really heard people doing migrations with are the Aedui. I guess they load all of their beginning troops onto the boat they start out with and send them off to Britain. You could do the opposite with the Casse and just leave right away. I imagine the Belgian territories would be good because they're homeland provinces for the Casse.
For migration campaigns that I've done, one time I had a KH game where I sent all of my troops to Krete. I didn't really like that game though because I had to destroy the Colossus of Rhodes and the Mausoleum at Halicarnassus to get enough starting money. It kind of ruined the experience. I guess I could do it again and purposely get more family members killed in the battle on Krete, but I don't know if it'd work. Once I build up my economy enough on Krete, I was making about 2000 mnai a turn. I saved up for a while and expanded by taking Kyrene, but I quit that game after a while.
I bet a Massilia or a Sinope game would be the most fun.
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