I've been playing Rome: Total War, and I've never actually played a strategy game before, so I decided to play on medium difficulty. Well, it turns out that medium is too easy. I played as Julii, and now I have over 200000 denari and over 30 provinces, but only one of my cities is big enough to recruit Triarii yet, and I can already attack Rome if I wanted to. At this point, I have tons of diplomats and just bribe away any enemy armies that can hurt me.

I'm thinking of going to a higher campaign difficulty on a new campaign (battles are hard enough for me right now), but I don't know if I should make it hard or very hard. So should I play on hard or very hard? What's the difference between the two?

Very Hard is difficult, and Hard is basically the norm as far as I can tell.

Very Hard increases the AI's strategies even moreso than Hard or something akin to that.

Despite having played Rome to death I have never known what it is exactly that the higher difficulty levels do. I thought it just gave the AI factions a [censored]load of free gold every turn, decreased the chance that AI factions declared war on each other and made all of them hate you. Like, really hate you. So no special strategies, just a whole lot of huge armies.