I agree completely that the outings can have a strong sense of foreplay. Casual references to what may be to come can keep anticipation at a high level.

Another thing is that a "semi" break as you say doesn't always have to be a stop to all play or an outing. Any easing of intensity etc can be a break. In my case I'm a big fan of bondage so being left for an hour or two in strict restraints and perhaps a hood can constitute a "break" while maintaining the D/s vibe. Maybe something relatively comfortable like a bondage bag or straitjacket? Maybe just in shackles and caged?

That gives the Domme a bit of a break too. With a good quality baby monitor she could go off to another room, get comfortable, have a meal, watch a show, work online....whatever.