ok - my advice is as follows. Get new photos done and work really hard at them. Abandon all principles of making it look 'lived in' or like a 'real family home' as that hasn't worked for you so far. Go completely shamelessly for the show home feel.
You should lead with the kitchen as that is definitely the best room. Remove absolutely everything from the worktops and the casserole dishes from above the units. Remember, you don't need to put everything away, just move it onto the floor in the coridoor, take the photo, and move on. The only things you should have on the work top are a vase of flowers (all one type, suggest all white tulips in a glass vase). And a bowl of fruit (again, all one type, suggest apples or lemons). Take that thing twiddly thing away from the window.
Next photo: the conservatory. Remove the bamboo thing, it doesn't photograph well. If possibly pain the wall white. Unfortunately the tablecloth is clashing with your floor in the photo. Probably change to a white tablecloth or a more brightly coloured one (pink, green). Take everything off the table and again, put a single vase of plain flowers in the middle.
Next photo: exterior of house. If possible paint the front wall. Can you add a white door number to the front door? Might break it up and make it look more inviting. Otherwise it's fine.
Next: living room. Remove the armchair and side table with lamp from the corner and put the pink toybox in the corner instead, lid on firmly (remove toys until it shuts). Remove everything from the shelves except speakers on the top shelf, one photo frame and a group of 3 white candles on the next shelf, record player and no more than 10 CDs lined up on the next shelf. nothing on the shelf-like thing under that. Remove the wooden bookcase from under the shelves. Remove everything from the mantlepiece and put one photo frame and one white candle on it instead. Remove the wicker waste-paper basket from next to the sofa. Switch the wall lights on when you take the photo.
Next: garden. Looks nice, sweep up the excess leaves on the path. Possibly put something like a small pot-plant on the table.
Next: bedroom. Take everything off the shelves and if possible remove the hanging storage thing under them. Put the blue picture on the top shelf not on the wooden panel thing. Leave the single seashell on the wooden panel, in the middle. Add a brightly coloured throw (borrow one off a friend if you don't have one) to the bed and pull the bed covers very hard at either end to make the duvet cover really uncreased. Take everything off the window cill.
Next: nursery. Looks generally nice. Take mobile off cot and remove all hanging and lurking stuff from the whole room including the grobag on the side of the cot and the clothes on top of the stool. Remove the white box that is sticking out into the room and the toy on the floor. Take everything out of the storage bags on the side of the changing unit. Now put the throw on the cot as though it is a duvet and put one really nice soft toy on top of the wooden stool. If you like put one adorable babygrow on a tiny coathanger hanging from the wardrobe door.
Next: bathroom. Remove all toiletries from the window ledge and instead put in a candle and your poshest bottle of bubble bath. Remove bathplug from photo.
Finally: two more exterior photos. They should be fine, not the greatest but would cost too much to really deal with this.
Not sure why this post is so long - probably shows something strange about my psyche! Good luck selling your house.