Romantic scenes I can live with but I agree that sex scenes are generally not required. If a couple who fancy each other start to take their clothes off we know pretty much what they're going to get up to, we don't need to see it. A quick edit to the aftermath of the 'action' would generally suffice IMHO.
I never saw the point of Regan & Carter traipsing out to Malta in the dust and heat to draw a blank in their enquiries before trailing all the way back home to Blighty during the film Sweeney 2. Seemed like pointless padding which did nothing to move the plot or action along from what I recall (but I haven't watched it in years to be honest).
How about the Montenegro casino sequences in Casino Royale (Craig). OK so it's theme is Casino...and JB has always been a dab hand at making a penny or two at the tables, but this whole interlude is waaay too long IMO and could easily be shortened. It really does make this central section of the film boring.