- If you want to save some money and you are 100% sure you won't arrive late at the track, get tickets in advance. Otherwise pay the walk-up, top fare and buy your tickets on the day of travel. Trenitalia or Italotreno, whichever is cheaper on the day and leaves earlier.
- Yes, if you go with Italo from Venice to Bologna and with Trenitalia from Bologna to Ravenna. If you are going all the way to Ravenna on Trenitalia, you'll get 2 PNR codes when purchasing online. If you get tickets Locally, the tickets machine will tell you how many tickets it's printing. Not the kind of thing one needs to know in advance.
- It depends on the trains, not on the route. If you take an high speed (Trenitalia's Freccias and all Italotreno's trains) or an Intercity train, you'll always be assigned a seat. On Regionale trains there are no reserved seats.
- Some transfers are at Ferrara, others at Bologna. Strange you are seeing more transfers at Ferrara, most high speed trains stop at Bologna. There are lifts and escalators at Bologna. I have no idea about Ferrara, but since it can't be a terminal station there will be underpasses to transfer between tracks.
- At the worst you'll have to wait some time for more cabs to arrive. Just exit the station, cabbies call their colleagues via radio if they see people waiting.
Incidentally, you can get tickets online even inside train stations and airports. Getting tickets on the day doesn't mean at the counter/ at the ticket machine.
Trenitalia's Regional tickets locally purchased can be used on any Regional train running that route on the picked day, the downside is that each Regional ticket must be time-stamped before getting on.
