I really like it, and it seems a lot of house for the money, but I'm not familiar with the Nuneaton property market, and haven't read the full thread, so apologise if I'm repeating suggestions from other commenters.
As far as decor goes, it is fairly neutral, and TBH most people want to do their own thing, so it doesn't seem worth the hassle of re-doing something which is never going to appeal to everyone.
Looking at other comments, I agree that the conservatory could do with jazzing up, and wonder if you know anyone with a couple of nice big potted palms you could borrow to put in there. Enough to show it off, but not so big as to hide the generous room size.
Likewise in the garden, people will have their own desires for the space, so I'd just give it a lift with a few strategically placed planters - primroses and spring bulbs are pretty cheap to get hold of right now, and offer lovely bright colours.
Re the door into the other bedroom, perhaps that's about marketing it either as a great nursery or potential dressing room. As it is there are options, if someone doesn't want the additional door they can always lock/block it.
The coffee table in front of the burner is awkward, and you could brighten the decor with a nice rug in it's place.
That's all I've got because I rather like it, and it only takes that one person to feel the same way. I hope you find a buyer soon.