Yep, you are absolutely on the right track - funk it up and it will work anywhere.

I'd put the day bed in the opposite corner behind the door going lengthwise to the window. The day bed will be too high for the low window and may look odd. Plus, i think the change will allow for better wardrobe and drawer space. As it is going to double up as a guest bedroom, do you really want all of your stuff on show with open shelving? I'd maybe try the Ikea Pax system, easy to buy what you want and fairly easy to construct, but i would have doors. You have to decide between walk in wardrobe or bedroom with wardrobes. Alternatively, maybe consider a high bed with wardrobes and storage underneath with extra on the other walls. By having something purpose built it will allow for more versatility and more floor space. They certainly don't have to be childlike these days. I'd post dimensions if i were you,

Re-cupboards and storage, it depends on your style. Have a look at Ikea Pax, you can probably put in a corner unit............I don't know what your dimensions are. but they do allsort. The doors with the cork finish are good for a lounge as they make them look less like a wardrobe. Also, you could have one door with a mirror on it and cut down on wall space for a mirror elsewhere. Same with the desk area. If you have an office in a cupboard you get extra storage, you can also close the doors to make it look really tidy.

Ah sorry, my bad. I thought (mistakenly?) I could drop the formalities, being among friends. Yours sincerely E D 😊