It's all a compromise, there's no single best option. I've used good quality wool, synthetics, and blends. The the blends I've had (Rab Cocona and Outdoor Research Sequence) tend to not be as soft as either synthetic or wool under heavy loads, in the hips and lower back. I've gotten bloody from the shirt grinding my skin up on 100+ pound packouts. Overall I prefer wool against my skin, but if hunting in more humid environments I might not. Synthetics are always going to move moisture more effectively and dry faster. For me, using light wool that dries fast enough, but still offers improved feel (in my opinion) and comfort through a wider range of conditions is my sweet spot. A lot of it is just personal preference.