Eaz-lift elite weight distribution hitch and air bags

Hey guy's I know this has been discussed before but here it goes.

I have a 2012 gmc 1500 with tow package. I've been to the CAT scales and I'm within my limits but at the high end, about 200-300 pounds from my payload. Trailer is 6500 pounds fully loaded.

With the eaz-lift wdh hooked up my front axle is back to normal ride height, and 80 pounds lighter than when not hitched to the trailer. The rear sags about two inches.

I get some porpoising when I hitting larger dips or bumps.

I ordered some Firestone airbags to fix the sag issue but I'm now thinking this may be normal and have also read that bags are not needed.

1. Should I try to readjust my hitch to help the rear end sag?

2. Go with the air bags? (I don't mind spending the money and know they will not help distribute the weight but think I'm OK there.

3. Just live with the sag? (it's a 1/2 ton and that's what they do) I'd love a 3/4 ton but not right now.

Also my eaz lift hitch has no washers but has what looks like an adjustment bolt which I do not see in any of the manuals (hitch was setup by the dealer and looks like it does not have any tilt, sits level) .

Also my trailer sits nose down, not bad but definitely not level. I've had zero sway issues (use the sway bar as well), I feel a little push with a gust of wind or passing big rig is all.

Any help would be greatly appreciated.