Bob have you considered adding the deleted scene of Yoda, ObiWan and Mace talking about arresting Palpatine before Grievous death instead of the one the film finally included?(it requires heavy edit of cheese, btw) I think it would add some nice touch to show that there's this "high command" of Jedi who are planning something, then cut to something else, then back the Council reunion where they don't say a thing aboute their plan, so that there's actually some "plot" to overthrow Palpatine right after Grievous death.

And about what I mentioned before about "Are you threating me?" line, what if you reduced the dialog drastically... Mace and the gang come to the office.

"In the name of the galactic...you are under arrest" (or they could even say nothing at all! and just ignite their sabres)
Palpatine, looking outside in his chair: "muahahaha (creepy laughter from ROTJ)... It's treason... then" (he stands up, and lights go off as you planned and the fight starts)