That is a great house.
I once moved in to an 'untouched since 1963 when the current owner bought it' Victorian terrace. Bakerlite switches, layers of wallpaper and LOUD carpets....Not as in your face as that property OP, but none the less full 1960's and 1970's colour and patterns (blue bathroom suite included).
The day I moved it I basically got a bunch of mates to pull up the carpets (they smelled...) and helped me put white paint on every wall surface possible in every room. It meant that I could live in it for a year without getting dizzy and slowly renovate and decorate each room. While white was bland, it helped show the different light levels, showed damage to walls etc. It was actually a really nice way of renovating as I 'got to know' the house - and ended up with the kitchen in a different room so I could get sunsets over the garden from the dining table.
Outside - I think you could paint the windows and railings white and it would look good.