Cast time is irrelevant. It is 0.7 seconds which can easily be generated by standing back or dodging or a quick push. Even when surrounded there is no issue casting the career skill.
And no the cooldown is 40 seconds (unless Ranaldsgift.com has the wronge value). 60 seconds is the cooldown for a Cluster of Radiance. Which brings us to the next problem that you have to career skill bars which allow a spam each 30 seconds if you want to. And this is before we are talking about cooldown reduction by getting hit, damaging enemies, using Hekarti’s Cruel Bargain or a simple cooldown reduction on the Trinket. The area affected is large enough and the most overtuned aspect of bloodrazor is certainly its damage. If you have a tool which can kill multiple Stormvermins on the spot with unlimited cleave then it is an issue.
The stagger is the actual only interesting and fun part of Bloodrazor and is what it should have concentrated on: Stagger for control, a prolonged but less severe bleed and far far far less direct damage. High damage and unlimited cleave is always a problem.
I agree though that Doomsight and Radiance are also in for some kind of adjustment.