read carefully what im about to say, write it down if needed

1st step- RESTART UR CAMPAIGN ON HARD/MEDIUM, the game was designed on medium state wise
(hard,very hard unbalances game with humongous + stats for ai)

i recommend after conquering athenai, to put a type 3 to milk money out of it but also recruit some hellenic troops such as hoplites and peltast/theurophia and such. Sparta ill put a type 4 for about 30 years to build up the MICs and happiness buildings then destroy gov and put a type 3 and repeat to type 2.
On to Epeiros- I recommend using cheats to move it away, usually id move them over to sicily or pergamon (to roleplay them as pergamium or syracuse)

this might sound bad but i usually build up half toe happiness and MICS in there settlement using
process_cq and add money cheats and let them built the rest
usually i FD lilybium from carthage to taras and let them conquear the island and stalemate te romans (they'll send stack after stack, but after 10 or so years, will make occasional raids or 2)
then happi for you, conquear the world!! and let carthage/rome fight over sicilly

then I/d FD koinon hellene to bosphorus to make a recreation of bosphorion kingdom to keep those pesky sauromates away from my recuirintg grounds for scythian archers.

then you know the rest