I wouldn't say lower cost, magicka return, the cap being based on damage instead of amount of projectiles (to Scales, a light attack is equal to an Assassin's Will proc), and Major Heroism (especially considering DK could make much better use of the ultigen than Warden) is weaker.
Scales is worse and DK is still just discount warden in many scenarios.
Scales is worse and DK is still just discount warden in many scenarios.