I watched your charity stream and it looked like you were using a variant with backlash, inner storm and quickening?
It worked great for me!!! The backlash keeps your health pretty much full and the EP and Bell wrecks the crowd!
I haven't done MP10 yet but MP8/9 was butter. One thing I noticed was that the mob sometimes die before I even got the bell off :) That made me think of how to maximize that inefficiency. Maybe empowered wave instead of wall of light; that may help control spirit too.
So I came here to read though and get some more info and insight and saw you noted strong spirit rather than flesh is weak. This indeed may be the key!
I'm rambling, as I type this I'm thinking empowered wave may help not "waste" any dps when dealing with trash, but it's really all about elite kills...so maybe not :)
I need to form more cohesive thoughts before typing, but by now I did all this typing so I may as well hit submit, lol...i'm an idiot.