Larger caliper = larger pad = more friction = more heat = better stopping power until the rotor is fully heat soaked, etc, etc, etc.
For me, the availability of 4Runner parts plus the ease of installation made a winning combo.
Yes I had to trim the backing plate with an angle grinder’s cutoff wheel.
Nothing exact or precise about the cuts.
I would "buy it"....
Your solution is working for you so it is first hand experience, shared.
Also, from experience, Toyota braking systems are usually quite redundant.
I have tested Hilux and 200 series vehicles to 40% over GVWR, and passed R13 (cold and hot) for European regulation with OEM systems on numerous occasions.
Going with upgraded rotors like DBA or other good brands can help with heat dicipation and would probably last longer than OEM rotors, while staying within OEM spec.
I have found that most modern truck brake systems would not fit 15" wheels and some would not fit certain geometry 16" wheels.
Although going with increased diameter rotors is the best way to go with the minimum heat "cost" and max efficiency, it is sometimes not possible to find the correct tire and wheel combo to support your design (especially for high load of 120 and higher load index), which may push you to larger tires thus loosing the larger rotors mechanical advantage.
Then, you end up with very similar performance at a very high priced system for initial costs as well as maintenance costs.
To emphasize this point, I have decreased tire size on at least one project just so I could find a sufficiently weight rated tire which would pass braking performance tests (by reducing effective wheel radius) in comparison to rotors size.
This was done on an American made vehicle with many potential braking systems upgrades from Wilwood and other, but could not get and effective solution due to available tire sizes.
Realizing a new desined tire would cost over 1M USD, sends you back to find more creative solutions.
Sorry for the long jabber, just wanted to share my experience of the reality of the balance between theoretically best efficiency goals and real life parts availability, combined with with thorough performance tests and good synch for expectations with client and test authorities.
Good thread with much interesting details.
Good luck
Omri