This quote from the manual for my fridge was very useful:
"The refrigerator is made to operate within 3° off level side-to-side and 6° off level front-to-back (as looking at the front of the refrigerator). Operating it at more than these limits can cause damage to the cooling system and create a risk of personal injury or property damage. Make sure the vehicle is level before you operate the refrigerator."
I have an app for my iPad caller "Clinometer". I load it up and put the iPad on top of the counter above the frig. It tells me exactly how many degrees off level I am. When I started doing it this way I realized I was working a lot harder than I needed to to level the trailer.
I use Lynx Levelers although wood blocks work fine. I do a lot of camping in primitive campgrounds so I need a lot of blocks. Some of the sites are crazy unlevel. The Lynx are lighter and easier to carry.
You can also build a ramp out of them. They make a wheel chock that fits into the blocks.
I also use them to make a step if my door side is too high. They make a cap for the blocks that make them easy to walk on.
I think if I got a few more I could make a little house with the lynx blocks and just camp in that
If I see that I am unlevel side-to-side I will build a ramp and drive onto it. Then I use the tongue jack to level front-to-back. I have a stick-on level on the tongue which is very useful.
I find that with this method I can get as close to level as I need to be without the stabilizers. I just use the stabilizers to steady the trailer. Using the stabilizers to correct the level the trailer is a lot of hard work.