Hello again!

I find there to be some imbalance here. Some skills like the frost nova has close to no casting time and can easily be weaved in with other skills. On my shadow weaver it feels fluent and good to use the shadow nova between Slayer's Flurry. On the other hand, I have a bladestorm build, where I use among other skills Sovereign Shout which has a long cast time. I can also not cast it while holding bladestorm, I have to release the button and stop spinning. Then I can activate Sovereign Shout. This animation time / global CD doesn't feel good to me, and sadly, is also the case for potion use. I can not use my potion without releasing my bladestorm, and as with Sovereign Shout animation I end up standing still for a pretty long time, which in many cases can prove to be lethal, especially for a meele character.
I use Sovereign Shout on my shadow weaver as well, and even if it is better than for bladestorm, the time you basically are frozen in place is too long. Often times it is better for me to wait until after I clear a wave to shout, since I will loose so much health during the cast animation, while I could be life leeching. This feels weird for a skill that seems designed to be used in the middle of a wave, considering some of the buff you receive is modified by the amount of enemies hit.
I guess you can use the stun node on it to make it better, but having skill modifiers that are necessary for a skill to work properly is kinda counter productive in my opinion, similar to the case with auto targeting on the turret.
I think shortening the animation time / global CD where you basically are frozen should resolve this issue (same for potion usage), as well as making combat feel more fluent. As it stands now I literally feel it "breaking my rhythm" every time I use Sovereign Shout or a potion, which is kind of sad. It just kills a lot of the joy for me at least.
Another option, at least for potions, could be to let the animation play while your character is moving.

If it is intended that the bladestorm can not be cancelled by casting other skills I will not object, I guess it comes down to personal preference. It is just not my preference in this case.

Thanks again for reading,

Cheers