I wouldn't, holding onto Gibraltar and maintaining Naval superiority across the Atlantic is the easiest and most significant way that GB can contribute to the war effort against France/Spain in the early game. That and looting all of the smaller provinces across France and Spain.
If it works for you it's as good a strategy as any.
I tend to keep hold of Gibraltar and use it as a starting point for the conquest of the Spanish provinces, then the southern French provinces and then on into Italy. I leave the northern French provinces alone early in the game because it makes the end game more interesting.