The thing to do is to follow the circuit. After all the rule of the air require all aircraft in the vicinity of and aerodrome to follow the circuit or avoid it. Orbiting without ATC clearance is not following the circuit.
Approach will have co-ordinated your joining the circuit with the tower in advance. Furthermore, the zone is approach's airspace and that includes the circuit so approach will be aware if the circuit is active.
Flying onto the deadside when cleared to join on base leg is against the rules of the air.
Finally, ATC have no separation responsibility for VFR flights in class D airspace.....the pilot must look out and separate him/herself from other aircraft. ATC will assist with traffic information etc but when on base leg, the responsibility for separation from aircraft on final including B747s making IFR approaches rests with the pilot alone. ATC will provide traffic information and wake avoidance information (recomended spacing). Although this is a minimum and ATC may provide further assistance.
So taking the above, I would have joined base and final and if no landing clearance was received and the converdsation was continuing, I would go-arround at 200ft to make another right hand circuit.
One can not land without clearance except in an emergency.
Thats my $.02 worth.
DFC