The proposals form a 'fifth option' the BMA wants ministers to consider alongside the four choices put forward in the consultation (GP, 12 March).
Meanwhile, an RCGP response says three quarters of its members are against allowing patients to register with any GP regardless of where they live - one of the options put forward in the DoH consultation.
The BMA response says the DoH should consider formalising the process of operating 'flexible' boundaries to allow existing patients who move just outside a practice boundary area to stay with their GP.
It also advocates a simplified system of opening and closing practice lists and increasing the use of remote consultations.
Temporary residents arrangements should be updated to enable unregistered patients to book a visit at any GP surgery in England on an ad hoc basis, the BMA response adds.
GPC chairman Dr Laurence Buckman said: 'GPs are very worried about the proposals to reform practice boundaries being put forward in the government's consultation, because they will damage patient care.
'We do, however, want to address the needs of the one in 10 patients who aren't currently satisfied with the care they receive, and that's why we've put forward a fifth proposal for the government to consider.'
The RCGP said the 'most significant and overarching concern' of its members is that boundary reforms could fragment co-ordinated care.
It also raised concerns that removing practice boundaries could make the provision of general practice 'very unstable' and lead to an increased risk of vulnerable children 'falling through the net'.
Its 'preferred option' is to maintain the current system of 'limited walk-in services' and longer opening hours.
'We strongly recommend the development of GP practices working together in primary care federations as a way to offer improved service delivery and patient access in the community,' the RCGP response says.
'This has the potential to offer patients improved access and the flexibility over extended areas, including access to out-of-hours care.'