Pharaoh and Cleo are more along the lines of C3 with road blocks that work You will have build large monuments over a long, long period of time.
Zeus and Poseidon are on a differnet game engine and more of a myth based set of missions There will be new interfaces to learn with some C3 skills carrying over

thank you mouse

I want to get into these new games without getting too much info up front so that I can learn my own way you know? But obviously I want to actually play them without too much disaster!

I have downloaded stats and tables on both of them already from this site and others, but I expect I will as always be back with new questions

Pharaoh/Cleo is very much like C3, Farming is a touch eaiser to manage once you get the hang of it, building monuments as Mouse said is huge, roadblocks make building housing blocks a little eaiser.

Zeus is all about defeating Gods and Monsters and building a city to do so. In my opinion building a zeus housing block is very easy and is not the central challenge of the game. Zeus/Posiden have eposodic goals very unlike C3, a set of goals might be, 3 trading partners, defeat a monster, 500 people in townhouses. For me the part of Zeus that is hardest to master is the complex relations your city must maintain with other cities.

I have just started playing Emperor, so far it is like Zeus in goals and inter-city relations, but is much improved in many ways; graphics, better challenge in building stable housing blocks, and feng shui!

I'll add to previous comments, all of which are accurate observations, that Zeus is a somewhat more whimsical game. You'll see the various characters associated with buildings and crafts each doing the unexpected. Look at them closely for the humor programmed into their antics. Example: The watchman on the fire tower is looking in all directions for signs of a fire except behind himself where his clothes are ignited and burning.