Hi Jill, We have lived aboard for over two years now so have some experience in how much juice you need to run x y and z. Your proposed domestic battery bank is huge compared to ours - currently we have 3 x 125ah agm on the domestic side and have just had a Sterling Alternator to Battery charger fitted to help speed up the battery charging. We have a Candy washing machine and run all the usual non essentials (according to some folk on this forum) such as tv, sat box, computer etc etc. We have cont. cruised for two years with this set up, we have a Victron combined inverter/charger - 2500/12v to supply the 240v when out and about, this runs the washing machine no problem. My only thought would be to have a seperate charger and inverter rather than a combined unit. We have a Shoreline 12v fridge which is run 24/7, I would steer away from 240v fridges run from the inverter - we used to have a 240v fridge but we have found 12v much more frugal.
So to sum up - you have plenty of juice in your proposed battery bank, get a pure sine wave inverter 2500 or up, seperate charger, 12v fridge and if you like a Sterling Alternator to battery charger or other alternator regulator gizmo.
As for a generator - we have never felt the need for one.
regards - whammy