The Seleucids are very rich and they can turtle in quite effectively. I'm still wondering what's stopping a dual cav army to just starve out a city - either sally forth and be subsequently crushed, or stay inside and starve. Cretians/Rhodians are good but they will be whittled down as you can't replenish your stacks. Now if Egypt did not play aggresively yes that could be pretty advantageous. However army for army Eggies will trounce Nmidia. And the Pharaoh's lands are so much richer than those arid deserts Numida has that the Eggies can have two armies for each one of their neighbors.