My family has not so large ... flat

[englishhobby]

My family has ___ not so large, but comfortable, ___ well-planned flat in the centre of the city. - This is a typical example of sentences my students sometimes make. I know this sentence sounds unnatural and there's an article and a conjunction missing, but if I just put in an article, it won't solve the problem, as the setence will sound awkward anyway. I could rephrase it to sound better:

My family has a medium-sized house located in the city center which is comfortable and well planned.

The problem is that I want to correct my student's sentence with "minimal" changes, if you know what I mean. I want to keep almost all the words the student used and the structure of the sentence but put it in a "proper" way. Is it possible?

 

[Raymott]

My family has ___ not so large, but comfortable, ___ well-planned flat in the centre of the city. - This is a typical example of sentences my students sometimes make. I know this sentence sounds unnatural and there's an article and a conjunction missing, but if I just put in an article, it won't solve the problem, as the setence will sound awkward anyway. I could rephrase it to sound better:

My family has a medium-sized house located in the city center which is comfortable and well planned.

The problem is that I want to correct my student's sentence with "minimal" changes, if you know what I mean. I want to keep almost all the words the student used and the structure of the sentence but put it in a "proper" way. Is it possible?

My family has a not so large, but comfortable, well-planned flat in the centre of the city.
The above is grammatical. It's not ideal, but it does correct the sentence with minimal changes.

"I'd like a not too expensive, but powerful, well-appointed sports car."
"I have a not so big, but vicious, well-trained guard dog."