I'm about 6 hours from finishing my upgrade to medieval, but my classical army was:
4 cataphracts
15 archers
16 heavy vandals (infantry)
2 calvary raiders
1 miner
in my experience -- and i've attacked for quite a few hours with this army -- picking the proper base is the most important aspect of successful raiding.
i only picked medieval bases (where i was almost guaranteed to lose most of my army) if i could guarantee 60k+ gold.
otherwise, i was better off hitting classical or below bases for whatever gold i could get.
my strategy was:
- drop cataphracts in one or two spots.
- support cataphracts with 2-3 infantry
- support those guys with archers once garrisons/stables spawned
depending on the base layout, i'd try to rally to a catapult or ballista (rare, though, that the base i attacked would have a centralized ballista).
i'd drop a few more infantry if the initial ones got picked off by archer towers. otherwise, i'd start sprinkling them all around the base for quick destruction.
once defenses were down, or almost down, i'd drop my calvary raiders.
i'd only use the miner if i was able to get major gold (and there were high level walls) or if i felt confident he would survive.
i'd generally destroy classical bases with 5ish lost infantry and 1 or 2 lost archers.
rinse and repeat.
all of the above is what i did for "legit" raids. i did an equal -- if not higher number -- of "snipe" raids. during these raids, i'd see whether the storages were full or not. if not, and i thought the gold was in the caravans, i'd wait until the maximum number of caravans were accessible (not behind a wall) and drop my first heavy vandal. i'd take out whatever structures i could with my heavy vandals and then rally to the gold piles. i'd also drop a few vandals to run interference with the horsemen from the woods or any spawns -- the point wasn't to defeat the troops, merely delay them so they didn't stop my guys from sniping the gold piles. if i could get two rallys in to gold piles, i considered it a win, even though i'd lose 10+ infantry in the process.