Close powerfully – and say explicitly what you think the court should do.
Persuasive argument neither comes to an abrupt halt nor trails off in a grab-bag of minor points. The art of rhetoric features what is known as the peroration—the conclusion of argument, which is meant to move the listener to act on what the preceding argument has logically described. The concluding paragraph of a legal argument cannot, of course, be as emotional as the peroration of Cicero’s first oration against Cataline. But it should perform the same function appropriately for the differing context. It should briefly call to the reader’s or listener’s mind the principal arguments made earlier and then describe why the rule of law established by those arguments must be vindicated — because, for example, any other disposition would leave the bar and the lower courts in uncertainty and confusion, or would facilitate fraud, or would flood the courts with frivolous litigation, and so on.
The trite phrase “for all the foregoing reasons” is hopelessly feeble. Say something forceful and vivid to sum up your points.