Lots of good advice here, but I think
@Teri Mitti you should define what you mean by “overlanding”. Are you planning to travel around the world, or explore the mountains, deserts, and forests of the US on rough dirt roads, camping in dispersed areas? I do a bit of the latter in a stock Tacoma TRD OffRoad double cab with 5’ bed, a ground tent and basic “car camping” gear. I had a roof top tent and sold it; it may work for some, but I found the weight, setup/tear down hassles and lack of flexibility a poor tradeoff for its (few) benefits. I installed rock sliders because I had really torn up the rocker panels of a previous 4x4 I owned, but I don’t think I’ve ever touched them on anything rougher than brush yet. By the way, that previous 4x4 was lifted with larger tires, but without good sliders (unavailable back then) the lift was still not enough to prevent body damage, yet reduced the ride quality, handling, and fuel economy.
On my current Tacoma, I also installed slightly more aggressive tires, but only after the stock ones wore out, and I an under hood air compressor plus a few extra 12V outlets. For domestic use, keep it stock, keep it as small and light and simple as you can. Better to carry 100 pounds of extra water, food, beer - or gasoline - than 100 pounds of “expo” gear you don’t really need.
For international overlanding, other experts should chime in.