Hello OP. Firstly I think you and your family have a wonderful home. Inside and out. It is a fine example of a period mews house and I think that has to be the main take away. It is a very specific style of home that will always be of a higher price point given its history.
I do not know Cheadle but with a quick look on Rightmove, you can see the other properties you come up against price wise at the moment have a drive/front garden, however these houses are for the most part far more modern and in my opinion incomparable.
If I were in your shoes I would possibly look to market again with a fresh start in the summer. Allow your home to be forgotten for the time being and to be found again with new buyers on the hunt. You shouldn’t have to reduce your property at all, especially if two agents now have said that’s the right price. Whenever I see a property listed with more than one agent / a new agent in the same selling period I’m afraid I do wonder what the problem with the house could be. Even more so if I see a dramatic price drop.
If you were to re-market with new photos, the summer again would be a better time for your house/garden to really shine. I think you’ve presented your home beautifully but if you were to do it all again, I’d echo what others have said about a few potted plants outside. Throw open all the window coverings and turn on all the lights in every room for the photo from the outside, so the windows all look even and equally warm and welcoming. I’d also potentially take out all baby toys from the main floor spaces/bathroom. Not to hide that you have babies of course but just so it doesn’t seem like you haven’t got any storage / not enough room for toys.
The mezzanine room is a very quirky room. I think it’s very cool, however I think you could sell this room better. If space allows could you perhaps move the bed from the mezzanine level to the main level and the desk onto the mezzanine? A bed on show in any room gives an understanding of scope of a room a lot more than a desk and could help bring in more people to view. I also wouldn’t call this room bedroom number one. It implies it’s the master bedroom / your biggest bedroom and in the pictures the space seems limiting. Assumptions may well be made from the numbering that bedroom two and three must be a lot smaller than number one. Whichever bedroom is your bedroom you should call number one.
I haven’t read everything mentioned in the comments but I did notice you said you’ll be covering the orangery’s glass roof? I once saw a conservatory room on Rightmove with the roof covered and I wondered ‘what’s the bad view they’re hiding?’. An orangery / conservatory style room is a room first and foremost to enjoy the sun so err on the side of caution of adding anything to obstruct the sun that can not be retracted easily.
I think your home is lovely, your garden is a great size and the fact that you’re detached with side access and
on a quiet mews street with only a handful of neighbours - these are all pros. I can only imagine it’s a matter of timing at fault for this type of period property and also, as I think you’ve found from a lot of the comments, there is a smaller pool of people willing to give up modern luxuries such as drives to own a quirky slice of history, but they are out there, you just haven’t found them yet. Or they haven’t found you… yet! You bought it and fell in love with it. Others will too. Keep the faith. 🤎