Regardless of which was there first (the airport or the housing), general aviation is, generally speaking, regulated more to protect non-participants than participants. Rule 5 provides for this, but repeatedly (Barton, Biggin Hill, Southampton, most recently) does not work because pilots do not comply with it. The Authority doesn't prosecute, though, so that bit of the Rule is derelict and needs attention, either by way of prosecutions to make people comply, or by an acceptance that an aircraft which has suffered a power failure has some sort of 'right' to come to earth on someone's home...
I don't fly single-engined aircraft any more, but respect the opinion of a close friend who refuses to operate an SEP aircraft into or out of a number of aerodromes, including Barton, which he views as simply unsafe and, in respect of Rule 5, impossible to operate to or from lawfully.
Your post implies that pilots at Barton are not complying with Rule 5.
You are exempt from Rule 5 during take off and landing.
I would always instruct students to turn into the circuit at a safe height, not to high that you are over Eccles, and not to low that you compromise safety.
Barton in itself is not unsafe, what is unsafe is pilots, visiting or based, ignorance of its' surroundings and short runways.
As for Barton being in breach of Rule 5, no more so than at it's big sister down the road.
As you approach 23R at Manchester you pass within within 500ft of some houses. Is this a breach of Rule 5 or am I landing?
As for practice Efato's at Barton, they have never been allowed off 09/14.
For very obvious reasons. But you used to see a string of Fanstops on a summers evening from 27.
On a final note, I did not know Mr Dalglish other than in passing, but my thoughts go out to you your family and the other gentleman still in hospital.