Hello Micro102,
Love this game series, even with its many faults.
Robbers die often by attacking carts, either by mercs, rival family units or by the town guards, and I never have recieved messages about this. Protip: Robbing carts is a good way of pissing people off and having your head land on the chopping block, each time your robbers hit a cart, it counts as a crime and it decreases the family who owns the cart's respect/like of your family.
I have not come across any guides for other classes, but rogues have it very easy compared to other types. Less work, more earnings early on and combat unit employees. Protip: Theives guild is the best way to start making money without pissing people off too much, if you only deploy pick pockets..
Scholars: I would go with a doctor build or the preacher line:
Pesthouse is nice passive income. Manufacturing is secondary income, but not terrible micro management.
Churches are less passive income, but it still rakes in donations, especially if you give the sermons yourself and have good charisma
Manufacturing is good income, but requires more micro management, and the AI is not great, so if it is your only holding you must work the building yourself, rather than having the AI manage the business.
Having good charisma opens up lots of other avenues, politics being the most important source of income and power.
Edit: Shit made a mistake:
Patrons: lots of mirco management, but I would go with a farm/public house combo, grow wheat and make ale, that type of thing. There is some passive income also.
Again get into politics ASAP
Craftsman: the hardest to get started, maybe the highest income. You are dependant on raw materials, you will not be able to buy the source of raw materials (lumbermill, mine) without some skullduggery or luck. I don't think there is any passive income, but you have to play the markets with manufacturing. Every time you sell goods, the price degrades, supply vs demand, and you have to juggle what to make, when to sell and where to sell if you are playing on big maps with more than one town/city.
As to the expansions: They are really fun, especially Renaissance, which I think gives you access to all of the possible classes from the Pirates of the European Seas, not sure about that. But the game is not less buggy, but it allows for more diversity in gameplay. I would stick with the original until you start to get bored and look into buying Renaissance if you still like the game.