You could use axe but I find axe redundant. It's cripple move also gives you retaliation... well then whats the point of cripple? The retaliation is going to be wasted from kiting. Axe doesn't seem to generate enough life force for me either. I like the concept not the execution.
Imo axe 1 needs to give life force and keep axe 2 life force and same cd which would result in more death shroud dps usage instead of just flat out giving a dps boost.
Skill 3 retaliation needs to gtfo and grant fear for 1 second and after it ends cripple for 5 and increase cd to 18 seconds.
Marks shouldn't be blocked by default. Seriously how do you block a mark? Makes no sense really. Reapers mark needs a 35 second cd.