I mix and match I think every brand has stand out pieces.
First Lite is my pick for merino, I have a bunch of their base layers as well as heavier merino stuff. I have the foundry pants and the obsidian. The obsidian weren't as durable as I had hoped, the foundry are my new go to... I love the long zips for heat dumping, the fabric is abrasion resistant and dries fast, and I like the knee pads. I don't like FL rain gear way to heavy IMHO and the DWR doesn't seem to be great. Haven't used the puffies.
Sitka is bomb proof, but also in my experience heaviest in class for everything... just lots of extra pocket, zippers, or whatever. The Jet stream jacket is a great softshell, the timberline pants are also awesome... I wish they had heat zips.
I think you get a ton for your money with Kuiu, I have the attack pants and guide pants. The guide are great for later season hunting, my only gripe is they are a bit baggier than I'd like. Love the kuiu socks, the extra padding around blister prone areas are great.
For puffies and hardshell I tend to look towards mountaineering companies over hunting brands. OR and REI are good and at the cheaper end, Patagonia, Rab, and Arcteryx are the high end options.
Not sure what you have but for sept elk I did some Kuiu Attack pants, a FL merio base layer, a synthetic layer that's a bit heavier and then a OR or REI puffy.