Gear Compounding

how different do your road speed and trail speed need to be, and if you need a low starting gear for driving around town / towing?
Ithaca NY comes to mind being a hillside town in NY. I'ld want a 4 speed before transfercase gears since the off road is rather mild.
But if I were someplace else and needed the low off road and around town was fine i'ld do Tera's first.

 

I agree with much of what has been said, but I’ll add/reiterate this:
What is best for you depends on what you want to do and what your street vs trail terrains look like. It comes down to range and overlap.

If you’re doing a ton of freeway driving and the rubicon - two extremes - there’s not much need for intermediate gearing or overlap. A setup with high (numerically low) axle gears and a granny box and Tera Lows is ideal. Fast on the freeway and super slow where you need it.

On the other end of the spectrum, if you only drive back roads on the way to explore forest service roads, a stock setup is all you’ll ever need. Limited speed on the pavement, and super low gears would go unused or get annoying.

Personally, I do a lot of freeway driving, and most of my off-roading is forest service roads. But there are many times where my 40:1 CR is way too high, especially with a more modern 4cyl (I might have something in the works to… double… my options ). Aside from that desire, I’m extremely pleased with the range of gears between high range and low range.
My overall range is 4.1:1 to 40:1 with some decent overlap between ranges.

High range:
1st - 3.71 x 4.10 = 15.211
2nd - 2.16 x 4.10 = 8.856
3rd - 1.37 x 4.10 = 5.617
4th - 1 x 4.10 = 4.10

Low range:
1st - 3.71 x 4.10 x 2.62 = 39.9
2nd - 2.16 x 4.10 x 2.62 = 23.2
3rd - 1.37 x 4.10 x 2.62 = 14.7
4th - 1 x 4.10 x 2.62 = 10.7

My 3rd and 4th in low range are very similar to my 1st and 2nd in high range.

This overlap is important to me. It keeps me from constantly needing to switch from high to low range every time I come to a rough patch or straight stretch. That helpful overlap is increased with a granny gear, and lessened with extreme t-case gears. Just something to consider.