There's no space for more unit unless you want them in the lounge
Yes there are - eg you could put units round
the wall (next to the cloakroom), put wall units next to the extractor fan, extend out losing the overhand (breakfast bar?), and then wrap back. It’s perfectly possible to add more cupboard space there - but it comes down to cost obviously. It’s all moot though, because I hadn’t seen it’s not a new build - although I guess it could have been a Homes Under the Hammer type development where they do things as cheaply as possible for as big a profit as possible.