A few years ago, I watched an amazing programme where 6 different people tried a different duet each for six weeks. The woman who lost the most (just over a stone) was doing The Scarsdale Diet, an old plan from the 70s.
I bought the book, followed the plan, and lost 3.5 stone in 4 months. No weighing. No measuring. You just eat what he tells you to eat every day for 2 weeks, then follow an easier "maintenance" plan for 2 weeks, etc.
Sample food:
Monday
Breakfast - grapefruit or fresh fruit, 1 slice toast, black coffee.
Lunch - cold meat, tomatoes, salad.
Dinner - Fish or shellfish, veg, more fruit for pudding.
I loved it because it totally trains you to eat really healthily. It's not like SW where you spend your time trying to fit your existing foods into the diet; Scarsdale is really clean eating.
I kept the weight off for 8 years, till I quit smoking and piled 3 stone on in a year. I've just lost 2.5 stone on WW because I find it hard to do a diet more than once. But I eat the Scarsdale way even on WW and it works for me.
Good luck!