I like TPI's "4-Hour Tours", but The Unofficial Guide to Walt Disney World tour book has the best tours, hands down. They actually designed a pretty complicated program that uses various algorithms, such as the loading capacity of an attraction, to find the best possible touring plan for each Orlando park. For their most efficient plan, they allot 2 days to The Magic Kingdom. On Day 1, Splash and Big Thunder Mountain are first on the list. On Day 2, Space Mountain is number one. If you do not get to the parks early and get on those attractions quickly, no "back-to-front" touring is going to save you.
But if you prefer to sked the whole trip, the Unofficial tours are great. That level of control isn't my style, but to each his own.