Apart from the weirdly sited radiator, which i can only assume is AI, I agree that it's top heavy with way too little living space/too small a kitchen for the number of bedrooms.
I wouldn't buy a 'new' build house, but if I wanted one, I'd expect it to have either a kitchen diner or - if the kitchen is as small as that one - and adjacent dining room that could be knocked through.
The number of toilets isn't necessarily a no for me (we once owned a house with four, although it was a much larger house and better proportioned overall), but I'm not a fan of the way they are crammed into new builds.
I'm not a fan of the staircase location either. The cottage we purchased last year had stairs in the living/dining room, which wasn't ideal. But we swapped the living room and kitchen so the former is now tucked away behind a door at the rear of the cottage whilst the stairs are in the dining end of the kitchen which works better imo.