Admiral Cornwell was in both s1 and s2. Like many admirals she was into some shady stuff - c.f. Her involvement with the Klingon genocide plot at the end of s1 and her work with s31 in s2. Granted, she redeemed herself with the torpedo, but for a semi-present admiral, Cornwell was probably an atypical villain that was fleshed out more than the Klingons, Leland, etc.