Hi Robyn, your proposed layout looks good. Our one suggested consideration would be the entry point to your room from the hall. This will be you main traffic route into the space. If there is cooking or prep going on in kitchen then it could be effected with people walking through (or kids running). We would look at change the door position to be on same wall as the door into your front room. This would create extra wall space for kitchen units (by blocking up current door) while allowing an entry point thorough the casual seating area instead of busy kitchen

Morning, Extending the kitchen (and lounge) area out into the garden is a great way to make room for that extra bedroom. We have worked on many similar projects in the past. We are a London based kitchen company with a great eye for deign and making the most of all kitchen spaces. If you would like advice or to discuss further please do get in touch. It would be great to hear some of your requirements needed to be incorporated into the kitchen design to include appliances etc. would also be helpful to get a feel for the style and colours you are interested in. Please feel free to get in touch with us via houzz or by email lj@pad.london Libra

First question to me is: do you have a tight budget? If you don;t I would take the opportunity to open up your ground floor more - on the other hand if your budget is tight than look at the finishes, make sure you are selecting neutral/white/light tones - the plan is deceiving - let me know if you need help. M_

More information definitely needed, With large extensions planned we need a layout including the garden and showing the boundary. Were you hoping for permitted development?