His damage is hurt due to not having a triple Buster deck, which is true, but his 40% increase on all card types because of its Projection skill makes up for it. Hawkeye lasts for 3 turns, so critting hard and consistently is easy, given a set up for him. He's not top class, but he IS useful and strong by himself (1 turn evade, crit damage and gen up, and attack down by 10~30%), thus seconding Red Fel's statement about his versatility, which he has.
Plus, he is actually Satan, so he's cool and all that.
Nobunaga is also pretty strong against her niche. Especially against these servants. Due to stacking Riding + Divine trait. Other than that, she supports well her team on NP Gain (except herself), and has a strong crit-buff on a 50% (and heavy star weight on 600%).