I think the kitchen is already good sized, but the walls between kitchen and dining area makes it feel smaller, and the door to the utility steals some usable space. I'd open up the walls and you'll get enough space to put in an island. By closing the door to the utility, you can place up to 5 tall units up to the ceiling, which can contain pantry space, as well as a fridge/freezer, one or two ovens, you name it! And I'd merge together cloakroom and utility to make a large shower room with hidden washer and dryer, keeping only the current door to the cloakroom. Not sure if it makes sense, please look at the image. If you prefer to keep these separate, you can always install a "hidden" for to look like a cabinet in the kitchen, leading to the utility. Finally, you could move the sink under the other window, and open up a door to access the garden from the window where the sink is now. It looks like a lovely spacious house!

If money isn't an issue, I'd put the kitchen/dining into the existing Lounge - the conservatory could be the lounge area off of it. Existing dining room then becomes separate snug - or open it up to the new kitchen, maybe you don't need the conservatory too?? Existing kitchen can then be another separate room - snug/lounge/guestroom/office. I'd take part of it and make the utility room bigger and more useful though.