Not sure about the temps you mean by hot weather but I have been trying to find the best hot weather pants as well. A zone deer in northern California specifically. Triple digits regularly, even though I am not actively hunting during these hottest parts of the day I might be moving or enduring the heat, and it's best to have clothing that will help keep me cool.
Pants I have tried.
Kuiu Attack: Obviously too warm, side zips are amazing though. Like glue for burrs.
Kuiu Tiburons: Nicest pants I have found so far if they didn't also attract burrs. I am honestly surprised they do considering the feel of the fabric.
Kuhl Konfidant Air: Favorite so far. Burr-resistant material. Lightweight. All pockets are made of mesh acting like "vents". If they had side zips they would be perfect.
I have a pair of the new SG pants on the way, we'll see how they stack up.
An interesting resource to look at would be Deputy Seans guide to hot weather clothing on reddit.
Here's a link to his imgur album specifically about pants:
Not all of the non-hunting brands of pants come in neutral colors unfortunately but check some of those out.