Looking very good, especially if this is your first!
(Love the general configuration -- very 'wrangler.
)
A few comments:
1. Is there any reason the front/back wheels need to be live axle? You're not tensioning them. My suggestion is to make them dead-axles, and make them structural. I love something called a "tube axle" here -- 1/2" OD, 1/4" ID tube, with a 1/4-20" bolt running through it. It'll stiffen things right up around the wheels (where it really matters!).
2. I don't like using sheet-metal as standoffs for gearbox plates. I recommend you use standoffs there, though other (equally as experienced) mentors would disagree with me, and have, loudly. YMMV.
3. You've got loooooots of rivets in places where it doesn't matter. That vertical row of rivets in the front bumper? Yeah... you need less than half of that. Hit the top and bottom hole, then space a few out in between. Then again, it doesn't matter -- rivets are almost "free."
4. Your lightening pattern can be a LOT more aggressive if you want. Even if you decide to stick with rounds, you can add additional smaller holes around your big holes. Remember the bumpers will add a lot of strength if done correctly.
5. Since you've adopted a "no belly pan" design -- make sure whatever upper structure you add provides torsional rigidity (helps prevent cross-corner flex). You can test this by holding three corners down, and lifting the fourth.
If you have the opportunity, build it, test it, and tweak it.
This is a low risk design which you should feel comfortable going into a season "cold" with, but another revision of lessons learned is worth its weight in gold.
Kudos again for a great first design!
-John