Zader doesn't need Zidious. He's good, but honelstly, Vader, Palp, TFP are the core of that team. Usually boosted with Shore and one of Zidious and Boba. I am personally thinking of dumping my tank (my Shore is gimpy, so I use Han to not lose out too much on the TM reduction) and using Nihilus instead: I really feel the lack of dispells.
But it depends on your shard. I can make top 5 (usually can't beat the guys in the top 4) with my Zader team, but there are few Mauls, and the one I mostly have to contend with is not all that powerful (the other one has a pretty firm grip on #1). The thing I found most important is to give TFP every single little bit of speed that you can.
