At highway speeds (let's say 60-65 MPH), you should be around 2600 RPMs or so. Anything below that RPM will be lugging the engine.
From what I can see, you're lugging the engine since it's under 2K RPM.
No one says re-gearing is a requirement, but it will make your JK much more enjoyable to drive, I can promise you that.
Of course you'll never know what you've been missing until you try driving a JK that's been re-geared. It's then that you'll come back to us and say, "Wow, I can't believe how much better it is".
