Axles generally have a camber, meaning you shouldn't just "flip" the axle and axles also come straight or with a drop. During my 6x10 build, I swapped out the drop axle for a straight axle (gaining about 4") and when purchasing the new axle, I opted for an under spring mount (gaining both from axle radius and spring thickness ... about 8"), for a total of close to 12 inches of lift. I changed the tires from stock 205's to 225's giving me a little, but nothing to brag about here. Take a look at the build in my gallery ... total frame to ground clearance is almost 24" the original was just about 12"
One needs to remember that an "Offroad TT" is subject to where one really goes ..
Mild might be - 2-wheel drive, and high clearance is helpful, but not absolutely necessary.
Medium might be ... High clearance 4x4 is required for at least part of the trail.
Rough Goes up from here ... 4x4 and high clearance is necessary for most of the trail and you might better have a winch and hi-lift jack on-board.
I grew up in a Jeep and did a lot of offroad travel in southern AZ and even pushed the offroad to walking out ... more than once (Young and foolish). I still go offroad and love to lock them in where 4x4 & high clearance is necessary. I built a CT that will take me where I want to go prospecting without tearing up my TV (A K-5 Blazer with 12.5 x 33" Tires and stock height) and/or CT ... giving me 24" of ground to frame clearance all the way back. Not an expedition combo, but in my world it is offroad and I have seen jeeps turn around before they get to my camp.
I guess the point I am making is that some folks think of offroad as the need for a bit more clearance off the pavement and others require a serious articulating, short wheelbase, 4x4 with oversize tires, and a TT to allow traversing whatever terrain the expeditions requires. Most of the country is making it illegal to blaze your own roads, meaning we have to stick to what's already blazed. Anyway, with this in mind, one needs to decide where they are going to go and what they really expect from their offroad rig and TT. As I get older, sleeping in a stand up trailer is an option I do not want to give up. As they teach in school, jot down all your wants with all the pro's and con's ... Then take it from there.
There are some great rigs pictured throughout this site and I agree that serious offroading requires a serious TV and TT to match, but what is serious to one, may not be serious to another.
Have fun and be careful...