A couple of points:-

With any of the "Greek" 3, Epiros, Mak or KH, I'd say taking the whole of that Peninsula asap is almost essential for a sensible game. You know that any shared borders equals inevitable war, with the utterly illogical ai, so why postpone it?

Here's a quick Epiros game I've done twice (with minor adjustments) on Hard/Medium

Epiros:- Raze Taras of all improvements, set taxes to V high, leave worst unit behind, move others to Greek mainland, disband all but one boat...IMPORTANT, move spy into Taras, and keep him there.Take Pella and Demet on turn one. Very east to do, because the elephants mean no siege neccesary. After taking Pella (and razing Royal Tombs), move General and then combine units one at a time to siege Demet (do it this way, as most dont have enough movement points). Then use the Taras/Pella money to hire all mercs, use this Army to take Demet. Train best horse unit availabe in Ambrakia, send all towards Athens.Then on turn 2 immediately beseige Athens, taking it on turn 3 (after combining armies), as well as Chalkis. Then Corinth and Sparta on turn 4/5. There is normally a lone Mak general somewhere around Sparta. Kill him and Mak are eliminated.

By then, Taras may have been taken by Rome, but your spy will normally cause a revolt, and you get it back with a slave garrison, just in time for your now almost decent full stack to arrive and wade it's way up through Italy, hiring mercs as needed. Meanwhile, train a small stack in Greece to take Crete (you don't need many). KH can be left with Rhodes, it's something for the future (or just make peace with them now well out of the way). N.B.:- If their very old Rhodes FM dies on the first few turns, and they don't get another in Rhodes, then they too are eliminated on you taking Sparta.

An ultimate Blitz guide to taking Greece and Italy in as few turns as possible, although you have to be very good at winning battles with hardly any casualties. Lots and lots of hammer and anvil here, even in tight city streets, where it's a lot tougher. Oh and keep those elephants safe, they have about 40 battles worth of rubber on their tyres ;)