I thnk you should be able to use different types of caravan ( at different prices obviously); highly defended ornate caravan (goes slowly due to protection but very low chance of encounter) shabby undefended caravan ( the opposite fast with high encounter chance) and in-between so you can role play being rich or poor and have scenarios based upon it ( seriously what kind of bandit would attack a heavily defended caravan while an undefended one much more likely)
This!
Also, can I just throw out there that I don't want the oblivion style fast travel available in the game. It makes it too easy to jump around and miss out on so much! Or at least have an option when you make your character: Fast Travel (non carriage) enabled/disabled