if you want to only spend moderate amount of money, then your key is to raid.

raiding for resources will provide you with all troops, if you became good at it, you will produce 24/7 from all 4 buildings

maybe find close bot city beside you, ask around... or simply spy, write down, build your farms of dead cities around you.

drachmas you can use on deals 70-80% discount from time to time, maybe to get lvl 5 towers, or buy champion units, or buy another artisan to develop your buildings faster.

but even max upgraded buildings don't come even close to resources you gain from raiding, its like 1:10.

try to find cities where u can pick 50k resource sin 1 go, then learn to sue galley trick to boos tit up to 70-100k in future

happy raiding