The honest answer: budget more than you think. Here's what actually happens.
Just the two of you: 30 minutes minimum, 45 ideal. Fifteen sounds like enough until you walk to the location, do warm-up shots, get the real shots, change pose, change angle, change spot. Fifteen minutes gets you maybe one usable spot.
Wedding party of 14: 25-30 minutes. The math: get them all in frame (5 min just to wrangle), the big group shot, then split — bridal party with the bride, groom side with the groom, mixed pairs. Nobody talks about the wrangling time. It's the wrangling.
Family formals: 3-5 minutes per grouping. If you have 12 groupings on your shot list, that's 45 minutes minimum. Have a designated family member with the list calling names — your photographer is shooting, not herding.
My real-world template for what you described: 30 min couple → 25 min wedding party → 45 min family formals = 1h40min total. I'd block 2 hours and have buffer.