Hey Alex,
You don't need the pearls and heels - a quilted nylon house coat, fluffy mules and a bottle of gin are just as suitable!
I would stick with the Proline (or rather, let your housemates stick to it) - unless you're lucky, housemates don't tend to treat vintage machines with the sanctity the deserve! Besides, owning a vintage washing machine is a bit like owning a classic car, in that you should always be on guard for new noises/leaks/plumes of smoke etc, and parts can be an issue for anything more than a few years old, unless you're lucky.
A twin tub is a splendid idea though, and can always be wheeled wherever there's room for it when it isn't in use. And like you say, it saves having to mix colours, plus you can drop bits in part way through and spin a mixed load, taking out synthetics etc after 30 seconds. I've got a Hoover, but Hotpoints are easier to live with, with Servises (Servii?) Fitting in between, IMHO.
Like Al said earlier, Bosch tabletop dishwashers are worthwhile, I've owned a Hotpoint branded one for a few years, cost forty quid from the paper and it hasn't missed a beat. The only problem is the diddy size means that loading it is sometimes akin to playing tetris...