McMillan profiles as a big slot in the NFL after at least 89.2% of his snaps from the slot over the last two years. He isn't a burner with build-up speed. He was slower in close quarters in 2023 as he dealt with injuries, but he showed some flashes of a second gear in 2022. McMillan isn't a quick-twitch player, which is reflected in his 56th-percentile 3-cone drill and 61st percentile 20-yard shuttle. McMillan is at his best, working against off-coverage underneath. He doesn't have the raw speed or route nuance to be utilized as a consistent deep threat. When he was tasked with out and ups at Washington, he was always blanketed. McMillan can separate on posts via his build-up speed. McMillan doesn't play well through contact in his routes or at the catch point. He only secured 20% of his contested targets in college. He also has some technique and concentration drops (7.9% drop rate).