Who tows with a Tacoma?

Hard to know for sure from the shot but if you park on level ground the ball height and wdh tension should be set so that the trailer is level and the distance from the Taco's front wheel wells to the ground is the same as it was before you put the trailer on the hitch. Do this with the trailer and Taco loaded for travel. You can use a couple pieces of blue painter's tape on the fenders above the front axle to make that measurement easier. To be sure the trailer is level just measure from the ground to the body front and rear on both sides. 

Maybe it's because the pic is sooooo large, but, your rig appears to be seriously nose down. Just my opinion 

2013 Toyota Tacoma 4x4 with tow package and a v6. Going uphill keep the rpms down, lower gear if necessary...no temperature problems. We get 14 mpg doing 60-65...traveling all over the west every year.

I have the Nissan equivalent, The Frontier, and I tow a 195 with little issue when going into appalachian mountains steep long climbs, but who doesn't. 

2008 Tacoma 4x4 with V6 and tow package added trans temp gauge, never had a problem towing my 2017 178.