I must admit. It was quite funny.

I think good solution for this might be to reduce from total immunity to positional immunity. Example - You can't interrupt if Sniper/Gunslinger is standing with his cover in front of him and is pointing to you but you can interrupt if you get behind him where cover is less effective. My two cents.

Malgus isn't a neutral version. He wants to destroy the Republic much like any other Sith. He fallows the Sith code. Only difference between Malgus and the rest of xenophobic Empire is that Malgus thinks aliens can achieve equal status with rest of the Sith/Imperial if they are strong enough and fallow the Sith line of thinking. Rule of the strongest and etc. But in the end... he is still Sith.

Malgus failed to properly play Sith politics and his strategy was badly flawed. First - He started the rebellion using fleet that needs crystals that are only mined on one planet which is of high strategic importance to both Republic and the Empire he betrayed. He challenged two major powers in galaxy right off the bat with fleet that has significant weakness (crystal usage). Weakness that Empire/Republic was able to pounce on at once and defeat the upstart in short order. Second - His only effort to sway Empire soldiers and citizens to his cause was a global Holonet broadcast. First we have to take into account that "average" Empire citizen is a xenophobe because they have been raised in that way for at least a 1000 years. Besides that highest ranking Sith that he was able to recruit was Darth Serevin. Although influential I wouldn't call him a crucial figure in Sith Order. So he definitely lacked proper political backing for his rebellion to work. On top of that we have the Emperor. In the eyes of regular grunts and citizens he is the most powerful begin alive, has lived and ruled over them for 1000 years and now he is challenged by Darth that is not even on the Council?!? Come on! What did Malgus expect? To whole of Empire to rally to his cause, betray the whole hierarchy that has been in place since Great Hyperspace War. Even if he was optimistic about the defection numbers he still had to fight most of the powerful Sith in the Empire because he didn't bother to recruit or sway or even neutralize them before he blown off his plan with the broadcast and on top of that he had invigorated Republic breathing down his neck. In my honest opinion if the rebellion actually worked all he would have achieved with his stunt is protracted civil war in the Empire that would have resulted ultimately in total Republic military victory. The only realistic outcome was the one Bioware presented us with. Malgus getting thrown in the shaft. Now form the viewpoint of my character. I would not support Darth Malgus because he failed to see the big picture. Ultimately all he has done was weaken the Empire and aided the Republic. Same Republic that he also hates and wants to destroy. I liked Malgus in trailers, like the iconic image that is Darth Malgus. I even liked his way of thinking how Empire should function but after the stunts he did on Ilum I'm glad he ended up thrown down the shaft.