It sounds like you're looking for a suspension upgrade for your 2018 Pro that will allow you to run a larger tire and provide a small lift, while maintaining the compliant ride you've come to enjoy.

From your research, it seems that you've considered BP51s, Bilsteins, and Dobinsons as options. The BP51s have been known to have rust issues with the bearings, so that's something to keep in mind. The Bilsteins are a solid choice, and the 6112/5160 setup is a popular option for the older Pros. The new 8112, which was announced but not available when you were researching, may also be a good option.

As for the OEM Fox setups, they are known to be durable and perform well, however, it's hard to say how they'll hold up over time as it will vary from vehicle to vehicle. Buying a near new 4Runner and getting the take offs from that vehicle for a decent price might be a good idea.

Dobinsons offer a wide range of suspension options, and it can be overwhelming to choose one. It's recommended to consult with a professional to make sure you get the right setup for your needs and usage.

In your case, you mostly drive on paved and gravel fire roads and highways with pot holes, and also an annual trip to a beach house that requires 5-9 miles of driving on a coastline and slightly inland, but its all beach all the time. In this case, Bilsteins or the 8112 would be a good option as they will give you the lift and tire clearance you need while maintaining the compliant ride you're looking for.