Sounds like you are making a well thought out plan to attempt Wolf's Head. I'm sure you will be fine. Honestly, the day hiking from Big Sandy trailhead to the Cirque with a heavy pack is harder for me than climbing Wolf's Head. Take a full day of rest after the hike in. Or two days. Use that time to scout the approach and even cache some gear at the base to make the climbing day easier. Try to go later in the season when the approach and descent aren't choked with snow (your plan for late August/early September is a good choice).

Give the West Ridge of Conness in Yosemite a try. The first few 5.7 pitches are as hard as anything on Wolf's Head. The rest is a long simulclimb like Matthes, significantly easier than Wolf's Head. Good test of how you will react to a long day of climbing.

Good luck and have fun!